Nasal seal and respiratory interface

ABSTRACT

A nasal mask having a seal housing and a flexible nasal seal connected or connectable to the seal housing to define a mask cavity. The nasal seal extends between a face-contacting side and an outer side. The nasal seal has a contacting surface having an edge that defines a nose-receiving opening into the mask cavity and which is configured to seal about the user&#39;s nose. The nasal seal also has an under-nose support fixedly connected into the seal and which is configured to extend within the mask cavity and having a contact surface that is oriented to contact at least a portion of the under-nose surface of the user.

FIELD OF THE INVENTION

This disclosure generally relates to a nasal seal for a respiratoryinterface, and to a nasal mask interface or interface assembly includingthe nasal seal.

BACKGROUND TO THE INVENTION

Respiratory interfaces are used to provide respiratory gas or gases,such as air in CPAP therapy, to a user under positive pressure. A nasalinterface delivers gas to the nose.

The seal of an indirect nasal interface or nasal mask contacts the upperlip, the face on either side of the nose, and the bridge of the nose,and substantially encloses the nose. Such nasal interfaces are oftensecured to the head of the user with headgear. Often the nasal maskassembly comprises a T-piece frame for connecting to headgear thatinclude a pair of upper side straps and lower side straps that extendgenerally substantially horizontally across the side of the users head.The upper straps extend above the user's ears and connect to an upperpart of the T-piece frame in the user's forehead region, and the lowerstraps extend under the user's ears and connect to a lower part of theT-piece frame at or toward the nasal interface, or from the nasalinterface itself. While such headgear tends to provide a relative stablesecurement of the nasal interface to the user, it can be obstructive oruncomfortable in use. Single side strap headgears are known that areless bulky, but also tend to be less stable in securing the nasalinterface in a sealing engagement during use.

In this specification where reference has been made to patentspecifications, other external documents, or other sources ofinformation, this is generally for the purpose of providing a contextfor discussing the features of the invention. Unless specifically statedotherwise, reference to such external documents is not to be construedas an admission that such documents, or such sources of information, inany jurisdiction, are prior art, or form part of the common generalknowledge in the art.

SUMMARY OF THE INVENTION

It is an object of at least some embodiments of the invention to providea nasal seal and/or nasal mask interface including the nasal seal and/orrespiratory interface assembly which is improved in at least one or morerespects, or to at least provide the public or medical profession with auseful choice.

In one aspect, the invention broadly relates to a nasal mask interfacecomprising: a seal housing; a flexible nasal seal connected orconnectable to the seal housing to define a mask cavity, the nasal sealextending between a face-contacting side and an outer side, andcomprising: a contacting surface comprising an edge that defines anose-receiving opening into the mask cavity and which is configured toseal about the user's nose; and an under-nose support fixedly connectedinto the nasal seal and which is configured to extend within the maskcavity and having a contact surface that is oriented to contact at leasta portion of the under-nose surface of the user.

In an embodiment, seal housing is rigid relative to the flexible nasalseal.

In an embodiment, the contacting surface seals about the user's noseincluding across a portion at or proximal to the nasal bridge region.

In an embodiment, the under-nose support at least extends laterallyacross the nasal seal within the mask cavity between opposing sides ofthe nasal seal at locations that are isolated or displaced from edge ofthe contacting surface of the nasal seal.

In an embodiment, the under-nose support at least extends laterallyacross the nasal seal within the mask cavity between opposing sides ofthe nasal seal at locations displaced from the contacting surface of thenasal seal.

In an embodiment, the under-nose support comprises one or more extensionportions that extend from within the mask cavity and connect to the edgeof the contacting surface of the nasal seal in an upper lip region ofthe nasal seal.

In an embodiment, the under-nose support comprises at least a mainlateral portion that extends laterally across the mask cavity betweenopposing sides of the nasal seal.

In an embodiment, the main lateral portion of the under-nose support isintegrally connected to the seal at locations that are isolated ordisplaced from at least the edge of the contacting surface of the nasalseal.

In an embodiment, the nasal seal comprises a sidewall that extendsrearwardly from the contacting surface of the nasal seal, and whereinthe main lateral portion of the under-nose support is integrally orfixedly connected to opposing sidewall portions of the nasal seal.

In an embodiment, the under-nose support further comprises one or moreextension portions that extend from the main lateral portion toward andconnecting to the nasal seal at an upper lip region of the nasal seal.

In an embodiment, the extension portion or portions connect to the upperlip region of the nasal seal at locations in the upper lip region of thenasal seal that are isolated or displaced from at least the edge of thecontacting surface of the nasal seal.

In an embodiment, the extension portion or portions of the under-nosesupport are connected to the edge of the contacting surface in the upperlip region of the nasal seal.

In an embodiment, the under-nose support comprises a central extensionportion having a contacting surface that is primarily configured tocontact with at least a portion of the columella of the nasal septum ofthe under-nose surface of the nose of a user.

In an embodiment, the under-nose support comprises left and right sideextension portions that extend on opposite sides of the nasal seal andwhich comprise contacting surfaces that are configured to primarilycontact at least portions of respective left and right alar rims of theunder-nose surface of the nose of a user.

In an embodiment, at any location along the under-nose support, theunder-nose support is substantially thinner in the transverse directionrelative to its contact surface than the corresponding width of thecontact surface at that location.

In an embodiment, the flexible nasal seal is formed of silicone.

In an embodiment, the seal housing is rigid and formed from plastic.

In an embodiment, the nasal seal is removably connectable to the sealhousing.

In an embodiment, the outer side of the nasal seal comprises aperipheral channel that is configured to receive a complimentaryperipheral ridge of the seal housing to connect the nasal seal to theseal housing.

In an embodiment, a peripheral edge of the outer side of the nasal sealis overmolded to a complimentary rigid clip, and wherein the rigid clipis connectable to the seal housing.

In an embodiment, the nasal seal is permanently or semi-permanentlycoupled to the seal housing.

In an embodiment, a peripheral edge of the outer side of the nasal sealis overmolded to a complimentary shaped opening edge of the sealhousing.

In another aspect, the invention broadly relates to a nasal seal for anasal mask or interface, the seal formed of a flexible material andextending between a face-contacting side and an outer side, comprising:a contacting surface comprising an edge that defines a nose-receivingopening and which is configured to seal about the user's nose; and anunder-nose support fixedly connected into the seal and which isconfigured to extend rearward of the nose-receiving opening and having acontact surface that is oriented to contact at least a portion of theunder-nose surface of the user.

In another aspect, the invention broadly relates to a nasal maskinterface assembly comprising: a seal housing; a flexible nasal sealconnected or connectable to the seal housing to define a mask cavity,the nasal seal extending between a face-contacting side and an outerside, and comprising: a contacting surface comprising an edge thatdefines a nose-receiving opening into the mask cavity and which isconfigured to seal about the user's nose; and an under-nose supportfixedly connected to the nasal seal and which is configured to extendwithin the mask cavity and having a contact surface that is oriented tocontact at least a portion of the under-nose surface of the user; andheadgear comprising single left and right side straps configured toextend over the user's ears and which connect to the seal housing.

In an embodiment, the left and right side straps connect to respectiveattachment locations at or toward respective sides of the seal housing.

In another aspect, the invention broadly relates to a nasal maskinterface assembly comprising: a seal housing; a flexible nasal sealconnected or connectable to the seal housing to define a mask cavity,the nasal seal extending between a face-contacting side and an outerside, and comprising: a contacting surface comprising an edge thatdefines a nose-receiving opening into the mask cavity and which isconfigured to seal about the user's nose; and an under-nose supportfixedly connected into the nasal seal and which is configured to extendwithin the mask cavity and having a contact surface that is oriented tocontact at least a portion of the under-nose surface of the user.

In an embodiment, the seal housing is rigid relative to the flexiblenasal seal.

In an embodiment, the contacting surface seals about the user's noseincluding across a portion at or proximal to the user's nasal bridge.

In an embodiment, the contacting surface seals about the user's noseincluding across a portion of the nasal bridge in an area extendingbetween the tip of the user's nose and the center of their nasal bridge.

In an embodiment, the under-nose support at least extends laterallyacross the nasal seal within the mask cavity between connectinglocations at opposing sides or upper lateral regions within the nasalseal.

In an embodiment, the connecting locations at the opposing sides orupper lateral regions within nasal seal are isolated or displaced fromthe edge of the contacting surface of the nasal seal.

In an embodiment, the connecting locations at the opposing sides or theupper lateral regions within the nasal seal are displaced from thecontacting surface of the nasal seal.

In an embodiment, the under-nose support comprises one or more extensionor connecting portions that extend from within the mask cavity andconnect to the edge of the contacting surface of the nasal seal in anupper lip region of the nasal seal.

In an embodiment, the under-nose support comprises at least a mainlateral portion with two ends that extend laterally across at least aportion of the mask cavity between connecting locations at opposingsides or upper lateral regions within the nasal seal.

In an embodiment, the under-nose support further comprises one or moreextension or connecting portions that extend from the main lateralportion toward and connect to the nasal seal at an upper lip region ofthe nasal seal.

In an embodiment, the under-nose support further comprises a centralconnecting portion that extends between the main lateral portion and aportion of the edge of the contacting surface in an upper lip region ofthe nasal seal.

In an embodiment, the central connecting portion of the under-nosesupport has a contacting surface that is primarily configured to contactwith at least a portion of the columnella of the nasal septum of theunder-nose surface of the nose of a user.

In an embodiment, the central connecting portion of the under-nosesupport varies in thickness across is length from a thicker region atthe end connecting to the main lateral portion and a thinner region ator toward the end connecting to the edge of the contacting surface.

In an embodiment, the central connecting portion of the under-nosesupport comprises a central region of reduced width relative to thewidth at its ends.

In an embodiment, the width of the central connecting portionprogressively varies along its length such that it is substantiallyhour-glass in shape or profile.

In an embodiment, the main lateral portion of the under-nose support isintegrally connected at its ends to within the nasal seal at connectinglocations that are isolated or displaced from at least the edge of thecontacting surface of the nasal seal.

In an embodiment, the nasal seal comprises a sidewall that extendsrearwardly from the contacting surface of the nasal seal to the outerside of the nasal seal, and wherein the main lateral portion of theunder-nose support is integrally or fixedly connected at its ends to atleast opposing sidewall portions within the nasal seal.

In an embodiment, the main lateral portion of the under-nose support isintegrally or fixedly connected at each end directly to inner surfacesof the nasal seal.

In an embodiment, the main lateral portion of the under-nose support isintegrally or fixedly connected at each end indirectly to inner surfacesof the nasal seal via a respective rib that extends from the innersurfaces of the nasal seal.

In an embodiment, each rib comprises a panel of flexible material havinga first connecting edge portion that is connected to a portion of theinner surface of the nasal seal and a second connecting edge portionthat is connected to a respective end of the main lateral portion of theunder-nose support at another portion of its peripheral edge.

In an embodiment, the first connecting edge portion of each rib isconnected to a portion of the inner surface of the nasal seal thatextends between a thinner front region of the nasal seal located towardthe face-contacting side and which comprises the contacting surface anda thicker rear region of the nasal seal located toward the outer side ofthe nasal seal.

In an embodiment, the first connecting edge portion of each ribterminates at or toward a thinned edge region of the front region of thenasal seal that is located about the periphery of the edge of thecontacting surface, the edge region being thinner than the remainingportion of the front region.

In an embodiment, each rib is shaped or configured with a buckling axisor zone that allows the rib feature to buckle or bend under compressionapplied to the contacting surface of the nasal seal.

In an embodiment, the buckling axis of zone of each rib is formed by arecessed r 0 or zone of the rib.

In an embodiment, each rib has a substantially vertical orientationwithin the nasal seal.

In an embodiment, the ribs extend from respective upper lateral regionsof the inner surface of the nasal seal, one from each side of the nasalbridge region of the nasal seal.

In an embodiment, the nasal seal is formed of a material having varyingthickness across regions of the nasal seal, the nasal seal defined by afront region extending toward the face contacting side of the nasal sealfront an intermediate boundary and which comprises the contactingsurface, and a rear region extending toward the outer side of the nasalseal from the intermediate boundary, the rear region being thicker onaverage than the front region.

In an embodiment, h front region comprises a thinned edge region thatextends about the periphery of the edge of the contacting surface, thethinned edge region being thinner than the remaining portion of thefront region.

In an embodiment, the contact surface of at least a central portion ofthe under-nose support is oriented at an angle relative to a seal axisthat extends tangentially between outermost upper and lower contactpoints in a central region of the contacting surface of the nasal seal.

In an embodiment, the contact surface of the central portion of theunder-nose support is oriented at an angle in the range of approximately40° to approximately 80° relative to the seal axis.

In an embodiment, the contact surface of the central portion of theunder-nose support is oriented at an angle in the range of approximately55° to approximately 65° relative to the seal axis.

In an embodiment, the ratio of the overall height to overall depth ofthe seal housing and nasal seal when assembled together is in the rangeof approximately 1:0.8 to approximately 1:1.2.

In an embodiment, the ratio of the overall height to overall depth ofthe seal housing and nasal seal when assembled together is approximately1:1.

In an embodiment, the ratio of the overall height to overall depth tooverall lateral width of the seal housing and nasal seal when assembledtogether is in the range of approximately 1:0.8:1 to approximately1:1.2:1.4.

In an embodiment, the ratio of the overall height to overall depth tooverall lateral of the seal housing and nasal seal when assembledtogether is approximately 1:1:1.2.

In an embodiment, the assembly further comprises: a yoke connected orconnectable to the seal housing, headgear connected or connectable tothe yoke, and an inlet opening in the seal housing for connecting to agases supply conduit.

In an embodiment, the seal housing comprises a yoke channel extendinglateral across the exterior surface of the seal housing that isconfigured to releasable receive and retain the yoke.

In an embodiment, the yoke is curved along its length between its ends,having a concave inner engagement surface with the yoke channel and aconvex outer surface.

In an embodiment, the headgear comprises at least a pair of side straps,each one of the pair of side straps extending along the sides or cheeksof the user's face and over the user's ears, and wherein each side strapconnects or extends from a respective end of the yoke.

In an embodiment, a central portion of the yoke is received in the yokechannel of the seal housing and the lateral portions of the yoke oneither side of the central portion extend outwardly away from the sidesof the nasal seal.

In an embodiment, the lateral portions of the yoke are thicker in heightand/or width relative to the central portion of the yoke.

In an embodiment, the headgear is automatically adjusting headgear andthe yoke comprises one or more directional locks that interact with coreelements extending from side straps of the automatically adjustingheadgear.

In an embodiment, a conduit frame that is releasably received andretained in the inlet opening of the seal housing, the conduit framebeing connected or connectable to an end of the gases supply conduit.

In an embodiment, the conduit frame is a hollow body that is ovular inshape, and wherein the conduit frame is symmetrical such that is can bereleasably received and retained in the inlet opening of the sealhousing in either of two orientations that are 180 degrees apart.

In an embodiment, at any location along the under-nose support, theunder-nose support is substantially thinner in the transverse directionrelative to its contact surface than the corresponding width of thecontact surface at that location.

In an embodiment, the flexible nasal seal is formed of silicone.

In an embodiment, the seal housing is rigid and formed from plastic.

In an embodiment, the nasal seal is removably connectable to the sealhousing.

In an embodiment, the outer side of the nasal seal comprises aperipheral channel that is configured to receive a complimentaryperipheral ridge of the seal housing to connect the nasal seal to theseal housing.

In an embodiment, a peripheral edge of the outer side of the nasal sealis overmolded to a complimentary rigid clip, and wherein the rigid clipis connectable to the seal housing.

In an embodiment, the nasal seal is permanently or semi-permanentlycoupled to the seal housing.

In an embodiment, a peripheral edge of the outer side of the nasal sealis secured to a complimentary shaped connecting edge of the sealhousing.

In an embodiment, the peripheral edge of the outer side of the nasalseal is overmolded to a complimentary shaped opening edge of the sealhousing.

In another aspect, the invention broadly relates to a nasal seal for anasal mask or interface, the seal formed of a flexible material andextending between a face-contacting side and an outer side, comprising:a contacting surface comprising an edge that defines a nose-receivingopening and which is configured to seal about the user's nose; and anunder-nose support fixedly connected within the seal and which islocated rearward of the nose-receiving opening and having a contactsurface that is oriented to contact at least a portion of the under-nosesurface of the user.

In another aspect, the invention broadly relates to a nasal maskinterface assembly comprising: a seal housing; a flexible nasal sealconnected or connectable to the seal housing to define a mask cavity,the nasal seal extending between a face-contacting side and an outerside, and comprising: a contacting surface comprising an edge thatdefines a nose-receiving opening into the mask cavity and which isconfigured to seal about the user's nose; and an under-nose supportfixedly connected within the nasal seal and which is configured toextend within the mask cavity and having a contact surface that isoriented to contact at least a portion of the under-nose surface of theuser; and headgear comprising single left and right side strapsconfigured to extend over the user's ears and which connect to the sealhousing.

In an embodiment, the left and right side straps connect to respectiveattachment locations at or toward respective sides of the seal housing.

In another aspect, the invention broadly relates to a nasal seal for anasal mask or interface, the seal formed of a flexible material andextending between a face-contacting side and an outer side, comprising:a contacting surface comprising an edge that defines a nose-receivingopening and which is configured to seal about the user's nose; and anunder-nose support fixedly connected to extend within the nasal seal.

In an embodiment, the under-nose support at least extends laterallyacross the nasal seal within the mask cavity between connectinglocations at opposing sides or upper lateral regions within the nasalseal.

In an embodiment, the under-nose support comprises one or more extensionor connecting portions that extend from within the mask cavity andconnect to the edge of the contacting surface of the nasal seal in anupper lip region of the nasal seal.

In an embodiment, the contact surface of at least a central portion ofthe under-nose support is oriented at an angle relative to a seal axisthat extends tangentially between outermost upper and lower contactpoints in a central region of the contacting surface of the nasal seal.

In an embodiment, the contact surface of the central portion of theunder-nose support is oriented at an angle in the range of approximately40° to approximately 80° relative to the seal axis.

In an embodiment, the nasal seal is defined by the contact surface atthe face-contacting side and a sidewall portion that extends rearwardlyfrom the contact surface to the outer side of the nasal seal and whichterminates in an opening or connecting edge for coupling or connected toa complimentary seal housing.

In another aspect, the invention broadly relates to a nasal maskinterface assembly comprising: a housing comprising; a flexible nasalseal connected or connectable to the seal housing to define a maskcavity, the nasal seal extending between a face-contacting side and anouter side, and comprising: a contacting surface comprising an edge thatdefines a nose-receiving opening into the mask cavity and which isconfigured to seal about the user's nose; and an arrangement of biasvent holes in the seal housing, wherein the arrangement of bias ventholes comprises at least one upper array of bias vent holes extendinglaterally across an upper region of the seal housing, and at least onelateral army of bias vent holes extending down portions of the sides ofthe seal housing.

In an embodiment, each array of bias vent holes is a line array ofspaced-part apertures or holes extending into the housing.

In another aspect, the invention broadly relates to a nasal maskinterface assembly comprising: a seal housing comprising an inletopening; a flexible nasal seal connected or connectable to the sealhousing to define a mask cavity, the nasal seal extending between aface-contacting side and an outer side, and comprising: a contactingsurface comprising an edge that defines a nose-receiving opening intothe mask cavity and which is configured to seal about the user's nose;and a conduit frame that is releasably received and retained in theinlet opening of the seal housing, the conduit frame being connected orconnectable to an end of the gases supply conduit, wherein the conduitframe is symmetrical such that is can be releasably received andretained in the inlet opening of the seal housing in either of twoorientations that are 180 degrees apart.

In an embodiment, the conduit frame is a hollow body that is ovular inshape.

In another aspect, the invention broadly relates to a nasal seal for anasal mask or interface, the seal formed of a flexible material andextending between a face-contacting side and an outer side, comprising:a contacting surface comprising an edge that defines a nose-receivingopening and which is configured to seal about the user's nose; andwherein the ratio of overall height to overall lateral width of thenasal seal is in the range of approximately 1:1 to approximately 1:1.4.

In an embodiment, the ratio of the overall height to overall lateralwidth of the nasal seal is approximately 1:1.2.

In an embodiment, the ratio of the overall height to overall lateralwidth to overall depth of the nasal seal is in the range ofapproximately 1:1:0.6 to approximately 1:1.4:1.

In an embodiment, the ratio of the overall height to overall lateralwidth to overall depth of the nasal seal is approximately 1:1.2:0.8.

Each aspect of the invention above may have any one or more featuresmentioned in respect of any one or more of the other aspects of theinvention above.

The term “comprising” as used in this specification and claims means“consisting at least in part of”. When interpreting each statement inthis specification and claims that includes the term “comprising”,features other than that or those prefaced by the term may also bepresent. Related terms such as “comprise” and “comprises” are to beinterpreted in the same manner.

Number Ranges

It is intended that reference to a range of numbers disclosed herein(for example, 1 to 10) also incorporates reference to all rationalnumbers within that range (for example, 1, 1.1, 2, 3, 3.9, 4, 5, 6, 6.5,7, 8, 9 and 10) and also any range of rational numbers within that range(for example, 2 to 8, 1.5 to 5.5 and 3.1 to 4.7) and, therefore, allsub-ranges of all ranges expressly disclosed herein are hereby expresslydisclosed. These are only examples of what is specifically intended andall possible combinations of numerical values between the lowest valueand the highest value enumerated are to be considered to be expresslystated in this application in a similar manner.

As used herein the term “and/or” means “and” “or”, or both.

As used herein “(s)” following a noun means the plural and/or singularforms of the noun.

The invention consists in the foregoing and also envisages constructionsof which the following gives examples only.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the invention will be described by way ofexample only and with reference to the drawings, in which:

FIG. 1 is a schematic diagram of a system for providing a heated andhumidified gases stream to a user, such as in a continuous positiveairway pressure (CPAP) system;

FIG. 2A is a schematic diagram of a nasal mask interface secured to thehead of a user with an over-the-ear headgear configuration;

FIG. 2B shows a force diagram relating to the forces experienced by thenasal mask interface during use;

FIG. 3 is a schematic diagram of the nasal anatomy of the under-nosesurface of a user's nose;

FIG. 4 is a front or face-contacting side (or wearer side) view of anasal mask interface or assembly in accordance with a first form of afirst embodiment, and showing a nasal seal with an under-nose supportconfiguration with a central extension, seal housing and headgear frameof the assembly;

FIG. 5 is a rear or outer side view of the nasal mask interface of thefirst embodiment;

FIG. 6 is an upper front side perspective view of the nasal maskinterface of the first embodiment;

FIG. 7 is a lower front side perspective view of the nasal maskinterface of the first embodiment;

FIG. 8 is an underside view of the nasal mask interface of the firstembodiment;

FIG. 9 is a top view of the nasal mask interface of the firstembodiment;

FIG. 10 is a side elevation view of the nasal mask interface of thefirst embodiment;

FIG. 11 is an outer side bottom perspective view of the seal housing andheadgear frame of the nasal mask interface of the first embodiment;

FIG. 12 is a wearer side upper perspective view of the seal housing andheadgear frame of the nasal mask interface of the first embodiment;

FIG. 13 is a front view from the face-contacting side (or wearer side)of the nasal seal of the nasal mask interface of the first embodiment;

FIG. 14 is a rear view from the outer side of the first embodiment nasalseal;

FIG. 15 is a top view of the first embodiment nasal seal;

FIG. 16 is an underside view of the first embodiment nasal seal;

FIG. 17 is a first rear underside perspective view from the outer sideof the first embodiment nasal seal;

FIG. 18 is a second rear upper perspective view from the outer side ofthe first embodiment nasal seal;

FIG. 19 is a first upper perspective view from the face-contacting sideof the first embodiment nasal seal;

FIG. 20 is a second underside perspective view from the face-contactingside of the first embodiment nasal seal;

FIG. 21 is a side elevation view of the first embodiment nasal seal;

FIG. 22 is a cross-sectional view of the first embodiment nasal sealthrough a central line A-A of FIG. 13 ;

FIG. 23 is a front perspective view from the face-contacting side of asecond form of the first embodiment nasal seal in which the under-nosesupport configuration is fully de-coupled or isolated from the edge ofthe face-contacting surface of the nasal seal;

FIG. 24 is a front view from the face-contacting side of a first form ofa second embodiment nasal seal having an under-nose supportconfiguration with left and tight side extension portions;

FIG. 25 is a rear view from the outer side of the second embodimentnasal seal;

FIG. 26 is a side elevation view of the second embodiment nasal seal;

FIG. 27 is a perspective view from the outer side of the secondembodiment nasal seal;

FIG. 28 is a rear perspective view from the outer side of the secondembodiment nasal seal;

FIG. 29 is a front perspective view of a second form of the secondembodiment nasal seal in which the under-nose support configuration thatis fully de-coupled or isolated from the edge of the face-contactingsurface of the nasal seal;

FIG. 30 is a front view of a third embodiment nasal seal having a‘floating’ under-nose support configuration;

FIG. 31 is a rear view from the outer side of the third embodiment nasalseal;

FIG. 32 is a side elevation view of the third embodiment nasal seal;

FIG. 33 is a front perspective view from the face-contacting side of thethird embodiment nasal seal;

FIG. 34 is a rear perspective view from the outer side of the thirdembodiment nasal seal;

FIG. 35 is a side elevation view of a nasal mask assembly in accordancewith a fourth embodiment, shown in use on a wearer;

FIG. 36 is a perspective view of the fourth embodiment nasal maskassembly, and in particular showing the nasal mask interface comprisinga nasal seal, seal housing, yoke, and conduit frame, and the nasal maskinterface connected to a headgear and flexible gases supply conduit;

FIG. 37 is an upper perspective view from the outer side of the fourthembodiment nasal mask interface showing the nasal seal, seal housing,yoke, and conduit frame;

FIG. 38 is an upper perspective view from the front or face-contactingside of the fourth embodiment nasal mask interface;

FIGS. 39 and 40 show upper and lower perspective exploded viewsrespectively of the fourth embodiment nasal mask interface;

FIG. 41 shows a rear or outer side view of the fourth embodiment nasalmask interface;

FIG. 42 is a side elevation view of the fourth embodiment nasal maskinterface;

FIG. 43 is a front or face-contacting side view of the fourth embodimentnasal mask interface;

FIG. 44 is a top view of the fourth embodiment nasal mask interface;

FIG. 45 is an underside view of the fourth embodiment nasal maskinterface;

FIG. 46 is a cross-sectional view of the fourth embodiment nasal maskinterface through a central line AA shown in FIG. 41 ;

FIG. 47 is a front or face-contacting side view of the nasal seal of thefourth embodiment nasal mask interface;

FIG. 48 is a rear view of the nasal seal of the fourth embodiment nasalmask interface;

FIG. 49 is a underside perspective view from the outer side of the nasalseal of the fourth embodiment nasal mask interface;

FIG. 50 is an upper perspective view from the outer side of the nasalseal of the fourth embodiment nasal mask interface;

FIG. 51 is a side elevation view of the nasal seal of the fourthembodiment nasal mask interface;

FIG. 52 is a top view of the nasal seal of the fourth embodiment nasalmask interface;

FIG. 53 is an underside view of the nasal seal of the fourth embodimentnasal mask interface;

FIG. 54 is a cross-sectional view of the nasal seal of the fourthembodiment nasal mask interface through line. AB of FIG. 52 ;

FIG. 55 is a perspective cross-sectional view of the nasal seal of thefourth embodiment nasal mask interface through line AC of FIG. 47 ;

FIG. 56 is a cross-sectional view of the nasal seal of the fourthembodiment nasal mask interface through line AC of FIG. 47 ;

FIG. 57 is a cross-sectional view of the nasal seal of the fourthembodiment nasal mask interface through line AG of FIG. 47 ;

FIG. 58 is a close-up view of area AD of FIG. 56 , and in particularshowing the angular dimensional profile of a portion of the under-nosesupport of the nasal seal of the fourth embodiment nasal mask interface;

FIG. 59 is a rear close-up view of the under-nose support of the fourthembodiment nasal mask interface configured for a small-medium sized sealconfiguration, and in particular showing the radius of curvature of acentral portion of the under-nose support;

FIG. 60 is a rear close-up view of the under-nose support of the Fourthembodiment nasal mask interface configured for a medium-large sized sealconfiguration, and in particular showing the radius of curvature of acentral portion of the under-nose support;

FIG. 61 shows a rear close-up view of another form of under-nose supportof the fourth embodiment nasal mask interface, the under-nose supporthaving a modified alternative squarish-shape;

FIG. 62 shows a close-up upper perspective view of a central region ofthe under-nose support of the nasal seal of the fourth embodiment nasalmask interface, and in particular identifies a width dimension of aportion of the under-nose support for a small-medium sized sealconfiguration;

FIG. 63 shows a close-up upper perspective view of a central region ofthe under-nose support of the nasal seal of the fourth embodiment nasalmask interface, and in particular identifies a width dimension of aportion of the under-nose support for a medium-large sized sealconfiguration;

FIG. 64 shows a close-up cross-sectional view of a portion of thecentral connecting portion of the under-nose support of the nasal sealof the fourth embodiment nasal mask interface, and in particular anangular dimension of the central connecting portion for a small-mediumsized seal configuration;

FIG. 65 shows a close-up cross-sectional view of a portion of a centralconnecting portion of the under-nose support of the nasal seal of thefourth embodiment nasal mask interface, and in particular an angulardimension of the central connecting portion for a medium-large sizedseal configuration;

FIG. 66 shows a close-up upper view of a nasal bridge region of thenasal seal of the fourth embodiment nasal mask interface, and inparticular a valley region of the contacting surface for a small-mediumsized seal configuration;

FIG. 67 shows a close-up upper view of a nasal bridge region of thenasal seal of the fourth embodiment nasal mask interface, and inparticular a valley region of the contacting surface for a medium-largesized seal configuration;

FIG. 68 is an upper perspective view from the outer side of the sealhousing of the fourth embodiment nasal mask interface;

FIG. 69 is a lower perspective view from the wearer side of the sealhousing of the fourth embodiment nasal mask interface;

FIG. 70 is a rear view of the outer side of the seal housing of thefourth embodiment nasal mask interface;

FIG. 71 is a front view of the wearer side of the seal housing of thefourth embodiment nasal mask interface;

FIG. 72 is a side elevation view of the seal housing of the fourthembodiment nasal mask interface;

FIG. 73 is a top view of the seal housing of the fourth embodiment nasalmask interface;

FIG. 74 is a bottom or underside view of the seal housing of the fourthembodiment nasal mask interface;

FIG. 75 is an upper perspective view from the conduit connecting end ofthe conduit frame of the fourth embodiment nasal mask interface;

FIG. 76 is an upper perspective view from the seal housing connectingend of the conduit frame of the fourth embodiment nasal mask interface;

FIG. 77 is a top view of the conduit frame of the fourth embodimentnasal mask interface;

FIG. 78 is a side elevation view of the conduit frame of the fourthembodiment nasal mask interface;

FIG. 79 is a cross-sectional view of the conduit frame of the fourthembodiment nasal mask interface through line AL of FIG. 77 ;

FIG. 80 is an end view of the conduit frame of the fourth embodimentnasal mask interface from the conduit connecting end of the conduitframe;

FIG. 81 is an end view of the conduit frame of the fourth embodimentnasal mask interface from the seal housing connecting end of the conduitframe;

FIG. 82 is an upper perspective view of the yoke of the fourthembodiment nasal mask interface from the outer side;

FIG. 83 is a top exploded view of the yoke of the fourth embodimentnasal mask interface;

FIG. 84 is a top view of the yoke of the fourth embodiment nasal maskinterface;

FIG. 85 is an underside view of the yoke of the fourth embodiment nasalmask interface;

FIG. 86 is a front view of the yoke of the fourth embodiment nasal maskinterface from an outer side;

FIG. 87 is a side elevation view of the yoke of the fourth embodimentnasal mask interface;

FIG. 88 is a partially exploded front view of the yoke of the fourthembodiment nasal mask interface, and in particular showing the end capsof the yoke detached;

FIG. 89 is another partially exploded front view of the yoke of thefourth embodiment nasal mask interface, and in particular showing theend caps of the yoke connected to the yoke back;

FIG. 90 is a rear or inner-side view of the yoke front of the yokeassembly of the fourth embodiment nasal mask interface;

FIG. 91 is a rear or inner-side view of the yoke front of the yokeassembly of the fourth embodiment nasal mask interface, and shows thedirectional locks and filaments of an automatically adjustable headgearassembly;

FIG. 92 is a partial section view of an alternative configuration of theyoke assembly showing components of a headgear adjustment mechanism inaccordance with the fourth embodiment nasal mask interface;

FIG. 93 shows a method of coupling an end cap onto an end of the yoke ofthe fourth embodiment nasal mask interface;

FIG. 94 is a partial rear perspective view of the assembled end cap andyoke of FIG. 93 ;

FIG. 95 is an end view of a yoke end of the yoke of the fourthembodiment nasal mask interface;

FIG. 96 is a top view of the yoke end of FIG. 95 ;

FIG. 97 is a section view of the end cap coupled to the yoke end takenalong line AK in FIG. 95 ;

FIG. 98 is a section view of the end cap of FIG. 97 ;

FIG. 99 is a cross-sectional view of a directional lock of the yoke of efourth embodiment nasal mask interface, the lock shown in a lockedposition;

FIG. 100 is a perspective cross-sectional view of the directional lockof FIG. 99 in the locked position;

FIG. 101 is a cross-sectional view of the directional lock in FIG. 99 inthe unlocked position;

FIG. 102 is a perspective cross-sectional view of the directional lockin FIG. 99 in the unlocked position;

FIG. 103 is a perspective view of an outer side of a first form of afifth embodiment nasal mask interface, including a nasal seal, nasalseal housing with integrated conduit connector, and yoke;

FIG. 104 is an upper perspective view of the first form nasal maskinterface of FIG. 103 from the front or face-contacting side;

FIG. 105 is an outer side view of the first form nasal mask interface ofFIG. 103 ;

FIG. 106 is a side elevation view of the first form nasal mask interfaceof FIG. 103 ;

FIG. 107 is a side elevation view of the first form nasal mask interfaceof FIG. 106 without the yoke;

FIG. 108 is an outer side perspective view of the first form nasal maskinterface shown in FIG. 107 ;

FIG. 109 is an outer side view of the seal housing of the first formnasal mask interface of FIG. 103 ;

FIG. 110 is a wearer side view of the seal housing of FIG. 109 ;

FIG. 111 is a front or face-contacting side view of the nasal seal ofthe first form nasal mask interface of FIG. 103 ;

FIG. 112 is a rear or outer side view of the nasal seal of FIG. 111 ;

FIG. 113 is a side elevation view of the nasal seal of FIG. 111 ;

FIG. 114 is a cross-sectional view of the first form nasal maskinterface of FIG. 103 through line BB of FIG. 105 ;

FIGS. 115, 116 and 117 show a wearer side perspective view, front outerside view, and top view respectively of the yoke of the first form nasalmask interface of FIG. 103 ;

FIG. 118 is a perspective view of an outer side of a second form of thefifth embodiment nasal mask interface;

FIG. 119 is a side elevation view of the second form nasal maskinterface of FIG. 118 ;

FIG. 120 is an outer side view of the second form nasal mask interfaceof FIG. 118 ;

FIG. 121 is a front or face-contacting side view of the second formnasal mask interface of FIG. 118 ;

FIG. 122 is an outer side view of the seal housing of the second formnasal mask interface of FIG. 118 ;

FIG. 123 is a side elevation view of the seal housing of the second formnasal mask interface of FIG. 118 ;

FIGS. 124, 125 and 126 show a front perspective view, outer side viewand top views of the yoke of the second form nasal mask interface ofFIG. 118 ;

FIG. 127 is a cross-sectional view of the second form nasal maskinterface of FIG. 118 through line BC of FIG. 120 ;

FIG. 128 is a close-up cross-sectional view of area BD of FIG. 127 ;

FIG. 129 is an outer side perspective view of a third form of the fifthembodiment nasal mask interface;

FIG. 130 is a side elevation view of the third form nasal mask interfaceof FIG. 129 ;

FIG. 131 is an outer side view of the third form nasal mask interface ofFIG. 129 ;

FIG. 132 is a front or face-contacting side view of the third form nasalmask interface of FIG. 129 ;

FIG. 133 is an outer side view of the seal housing of the third formnasal mask interface of FIG. 129 ;

FIG. 134 is a side elevation view of the seal housing of FIG. 133 ;

FIG. 135 is a face-contacting side view of the nasal seal of the thirdform nasal mask interface of FIG. 129 ;

FIG. 136 is an outer side view of the nasal seal of FIG. 135 ;

FIG. 137 is a perspective view of the face-contacting side of the nasalseal of FIG. 135 ;

FIG. 138 is a side elevation view of the nasal seal of FIG. 135 ;

FIG. 139 is a cross-sectional view of the nasal seal through line BE ofFIG. 135 ;

FIG. 140 is an outer side perspective view of a fourth form of the fifthembodiment nasal mask interface;

FIG. 141 is a side elevation view of the fourth form nasal maskinterface of FIG. 140 ;

FIG. 142 is an outer side view of the fourth form nasal mask interfaceof FIG. 140 ;

FIG. 143 is a face-contacting side view of the fourth form nasal maskinterface of FIG. 140 ;

FIG. 144 is an outside view of the seal housing of the fourth form nasalmask interface of FIG. 140 ;

FIG. 145 is a side elevation view of the seal housing of FIG. 144 ;

FIG. 146 is a perspective view from the face-contacting side of thenasal seal of the fourth form nasal mask interface of FIG. 140 ;

FIG. 147 is a side elevation view of the nasal seal of FIG. 146 ;

FIG. 148 is a cross-sectional view of the nasal seal of FIG. 146 throughthe central line BF indicated in FIG. 146 ;

FIG. 149 is a cross-sectional view of the fourth form nasal maskinterface through line BG of FIG. 142 ; and including an overlay of thenasal seal of the third form nasal mask interface of FIG. 135 forcomparison as to shape and dimension;

FIG. 150 is a front or face-contacting side view of a sixth embodimentof the nasal mask interface, in particular showing the yoke beinglocated below the conduit frame or inlet aperture of the seal housing;

FIG. 151 is an outer side view of the sixth embodiment nasal maskinterface;

FIG. 152 is a side elevation view of the sixth embodiment nasal maskinterface;

FIG. 153 is an outer side view of the seal housing and yoke of the sixthembodiment nasal mask interface;

FIG. 154 is a face-contacting side view of the seal housing and yoke ofthe nasal mask interface;

FIG. 155 is a face-contacting side view of a first form nasal seal of aseventh embodiment of the nasal mask interface, in which the nasal sealcomprises wing portions extending from the sides of the nasal seal;

FIG. 156 is an outer side view of the first form nasal seal of FIG. 155;

FIG. 157 is a side elevation view of the first form nasal seal of FIG.155 ;

FIG. 158 is an outer side perspective view of a second form nasal sealof the embodiment nasal mask interface, in particular showing longerwing portions (relative to the first form) extending from the sides ofthe nasal seal;

FIG. 159 is a face-contacting side view of the second form nasal seal ofFIG. 158 ;

FIG. 160 is an outer side view of the second form nasal seal of FIG. 158;

FIG. 161 is a top view of the second form nasal seal of FIG. 158 ;

FIG. 162 is a perspective view of a seventh embodiment nasal maskinterface comprising the second form nasal seal being worn by a user;

FIG. 163 is a side elevation view of a first form of an eighthembodiment of the nasal mask interface in which the interface comprisesa forehead support extending from the nasal seal or seal housing;

FIG. 164 is a perspective view of a user wearing the first form of thenasal mask interface of FIG. 163 ;

FIG. 165 is a face-contacting side view of a second form of the eighthembodiment nasal mask interface in which the nasal seal comprises anasal bridge support protrusion;

FIG. 166 shows an outer side view of the second form nasal seal of FIG.165 ;

FIG. 167 shows a side elevation view of the second form nasal seal ofFIG. 165 ;

FIG. 168 shows a cross-sectional view of the second form nasal seal ofFIG. 165 through line EE of FIG. 166 ; FIG. 169 is a perspective view ofa user wearing the second form nasal seal of FIG. 165 ;

FIG. 170 is a side elevation view of the user wearing the second formnasal seal in FIG. 169 and showing a gap between the nasal bridgesupport protrusion and the user's nasal bridge;

FIG. 171 is an outer side view of a first form nasal seal of a ninthembodiment nasal mask interface, where the nasal seal includesadditional support ribs within the nasal mask;

FIG. 172 is a face-contacting side view of the first form nasal seal ofFIG. 171 ;

FIG. 173 is a cross-sectional view of the first form nasal seal throughline FF of FIG. 171 ;

FIG. 174 is a perspective view of the cross-sectional view of FIG. 173of the nasal seal;

FIG. 175 is a face-contacting side view of a second form nasal seal ofthe ninth embodiment nasal mask interface;

FIG. 176 is an outer side view of the second form nasal mask of FIG. 175;

FIG. 177 is a side elevation view of the second form nasal seal of FIG.175 ;

FIG. 178 is a cross-sectional view of the second form nasal seal ofthrough line of FIG. 175 ;

FIG. 179 is a perspective view of a user wearing the second form nasalseal of FIG. 175 ;

FIG. 180 is a side cross-sectional view of the user wearing the secondform nasal seal in FIG. 179 ;

FIG. 181 is a cross-sectional view of the first form and second formnasal seals of FIGS. 171 and 175 overlaid onto each other to show acomparison of shape and dimension;

FIG. 182 is a face-contacting side view of the first and second formnasal seals of FIGS. 171 and 175 overlaid onto each other for comparisonof shape and dimension;

FIG. 183 is an outer side perspective view of a third form nasal seal ofthe ninth embodiment nasal mask interface;

FIG. 184 is an outer side view of the third form nasal seal of FIG. 183;

FIG. 185 is a face-contacting side view of the third form nasal seal ofFIG. 183 ;

FIG. 186 is an outer side perspective view of a first form of a sealhousing and conduit frame assembly of a tenth embodiment nasal maskinterface;

FIG. 187 is an exploded view of the first form seal housing and conduitframe assembly of FIG. 186 ;

FIG. 188 is a side elevation view of the conduit frame of the first formassembly of FIG. 186 ;

FIG. 189 is a top view of the conduit frame of the first form assemblyof FIG. 186 ;

FIG. 190 is an outer side perspective view of a second form seal housingand conduit frame assembly of the tenth embodiment nasal mask interface;

FIG. 191 is an exploded view of the second form assembly of FIG. 190 ;

FIG. 192 is a side elevation view of the conduit frame of the secondform assembly of FIG. 190 ;

FIG. 193 is a top view of the conduit frame of the second form assemblyof FIG. 190 ;

FIG. 194 is an outer side perspective view of a third form seal housingand conduit frame assembly of the tenth embodiment nasal mask interface;

FIG. 195 is an exploded perspective view of the third form assembly ofFIG. 194 ;

FIG. 196 is a side elevation view of the conduit frame of the third formassembly of FIG. 194 ;

FIG. 197 is a top view of the conduit frame of the third form assemblyof FIG. 194 ;

FIG. 198 is an outer side perspective view of a fourth form seal housingand conduit frame assembly of the tenth embodiment nasal mask interface;

FIG. 199 is an exploded perspective view of the fourth form assembly ofFIG. 198 ;

FIG. 200 is a side elevation view of the conduit frame of the fourthform assembly of FIG. 198 ;

FIG. 201 is a top view of the conduit frame of the fourth form assemblyof FIG. 198 ;

FIG. 202 is an outer side perspective view of a fifth form seal housingand conduit frame assembly of the tenth embodiment nasal mask interface;

FIG. 203 is an exploded perspective view of the fifth form assembly ofFIG. 202 ;

FIG. 204 a side elevation view of the conduit frame of the fifth formassembly of FIG. 202 ;

FIG. 205 is a top view of the conduit frame of the fifth form assemblyof FIG. 202 ; and

FIG. 206 is a front view of a full face seal with an under-nose supportconfiguration in accordance with an eleventh embodiment.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS System Overview

FIG. 1 is a schematic diagram of a continuous positive airway pressure(CPAP) system 10 for providing a heated and humidified air stream to auser U through an interface 11 worn by the user, and which is connectedto CPAP system 10 by a flexible conduit or tube 12.

A humidification chamber 14 has a heat conductive base in contact with aheater plate 16 of humidifier 17 to humidify the air stream. Conduit 12is connected to an outlet 13 of humidification chamber 14 to conveyhumidified air to the user interface 11. The humidifier 17 comprises acontroller 18, such as a microprocessor-based controller that executescomputer software commands stored in an associated memory, for examplebut without limitation. The controller 18 receives input commands frommultiple sources, including a user input interface 19 such as a dial ortouch screen, which enables the setting of a predetermined value ofhumidity, temperature, or other characteristic of the humidified airsupplied to the user U. The controller 18 also may receive input fromone or more other sources, such as for example temperature and/or flowvelocity sensors 20 and 21, which are connected through a connector 22to communicate with controller 18, and/or a heater plate temperaturesensor 23. In response to the user set humidity or temperature value thecontroller 19 determines when and/or to what level the heater plate 16should be energized to suitably heat the water contained in thehumidification chamber 14.

As the volume of water in the chamber is heated, water vapour begins tofill the volume of the chamber above a surface of the water. The watervapour passes out of the outlet 13 of the humidification chamber with aflow of air that is provided from a supply 25 such as a blower 27, whichenters the humidification chamber 30 through an inlet 26. The blower 27can be variable in speed fan, or can include a variable pressureregulator. The blower 27 draws air through an inlet 28. The blower canbe controlled by controller 29 or controller 18 for example. Thecontroller may control blower speed, regulated pressure, or the likeaccording to any suitable criteria. For example, the controller mayrespond to inputs from controller 18 and a user set value (e.g., apreset value) of pressure and/or fan speed, which can be set with a userinterface 30 (e.g., a dial).

The conduit 12 may comprise a heater such as a heater wire for example,to heat the walls of the conduit to reduce condensation of humidifiedgases within the conduit.

The seal and interfaces of this disclosure can be used in such a CPAPsystem as described whether humidified or not, or alternatively in otherforms of respiratory systems, such as for example VPAP (VariablePositive Airway Pressure) systems, BiPAP (Bi level Positive AirwayPressure) systems, or with a ventilator, high-flow therapy system, andare described herein generally with reference to CPAP therapy by way ofexample only.

Nasal Mask Interface with Above-Ear Headgear

Referring to FIGS. 2A and 2B, a user U is depicted wearing a nasal maskinterface 50 in accordance with an embodiment. The nasal mask interface50 comprises a nasal mask including a seal 51 and a seal housing 53. Theinterface also includes headgear 52 for securing the mask to the wearer.Typically the interface also comprises a flexible supply conduit or tube55 from the mask such as from a central connection at the front orunderside of the mask, which is integral with or connects to the supplyconduit 12 of the CPAP or other respiratory system. The conduit 55 mayconnect directly to the mask or indirectly via a connector or conduitframe such as, but not limited to, a straight connector or a swivelelbow 34, which may swivel relative to the mask or seal housing so thatthe path of the conduit relative to the positioning of the mask on theface of the patient can adapt to the sleeping position of the patient.

As will be explained later, the mask may include a limited flow outletor vent (or bias flow outlet or vent) 57 for providing gas washout fromthe interface. The outlet 57 may be in the form of a collection of smallapertures. The outlet may be provided on the seal housing 53 as shown,conduit connector or frame such as an elbow or straight connector, orelsewhere on the interface.

In this embodiment, the nasal mask is secured to the user U by headgear52 that extends above the user's ears. By way of example, the headgear52 comprises side straps 54 that connect to opposing sides of the nasalmask interface 50 at attachment points 56 (only one side visible) andwhich extend along the sides or cheeks of the user's face, and over theuser's ears 58, and connect to one or more other straps or strapportions. The headgear 52 in this embodiment also comprises a top orcrown strap 60 that extends over the user's head or crown and a back orrear strap 62. The side straps 54 are integrally formed or otherwiseconnected to the top 60 and back strap 62 as will be appreciated by askilled person. In one embodiment the headgear straps are formed of orcomprise a flexible breathable material such as Breath-o-Prene®breathable neoprene material, or neoprene material, or similar. In someembodiments, the headgear may be automatically adjusting headgear,examples of which will be explained later.

The depicted above-ear headgear 52 with single side straps 54 attachingto respective side attachment points or locations on the nasal maskinterface 50 is a generally desirable configuration from a comfortviewpoint relative to a headgear configuration with a pair of upper andlower side straps that connects to a nasal mask interface having aT-piece frame. The above-ear single side strap headgear configuration 52depicted in FIG. 2A does not require a T-piece frame extending up to theuser's forehead and also eliminates the requirement for two pairs ofupper and lower side straps, one pair extending over the user's earsfrom the top part of the T-piece frame at the user's forehead, and theother pair extending from the nasal mask interface below the user'sears, as previously explained.

Referring to FIGS. 2A and 2B, while the above-ear single side strapheadgear configuration 52 is preferable from a comfort viewpointrelative to a headgear that is secured to a T-piece frame, it has beendiscovered that in use the forces acting on the nasal mask interfaceduring flow therapy in which the mask is delivering gases at positivepressure to the user's nose, the nasal mask tends to ride, slide or slipup the user's face, which can impact on the robustness of the sealingabout the user's nose and create leaks or leak paths. The riding up ofthe nasal seal can also be distracting and uncomfortable to the user. Ithas been discovered that the nasal mask interface experiences asubstantially diagonal force represented by vector A along the generaldirection of the side straps between a user's nose and above the earfrom each side strap, and a counteracting substantially horizontalblow-off force B forcing the nasal interface substantially horizontallyaway from the user's nose and face when a flow of positive pressuregases is being delivered to the wearer in use. The resultant force R ofthe headgear force A and blow-off force B acting on the nasal maskinterface in a substantially vertical resultant force represented byvector R.

As will be explained with reference to the embodiments below, the nasalmask interface of this disclosure is provided with a nasal seal havingan internal under-nose support that is configured contact or engageunder the user's nose to generate an opposing downward force D that atleast partially counteracts, resists or otherwise mitigates theresultant force R generated by the headgear force A and blow-off force Bto thereby stabilize the nasal mask in place over the user's nose duringuse and prevent its tendency to slide or otherwise move up the user'sface from its initially secured position prior to gas delivery beinginitiated.

Referring to FIG. 3 , the under-nose support of the nasal mask assemblyis configured to contact at least a portion or portions of theunder-nose surface 70 of the user's nose when wearing the mask. Theanatomy of the under-nose surface of a user's nose is generally definedby the central columella region 72 of the septum that extends betweenand divides the nostrils 74 from the base 76 to the tip 78 of the noseand the left and right alar rim regions 80. The columella 72 and alarregions 80 generally define the contactable skin surfaces of theunderside of the user's nose about the nostrils or nare openings 74.

As will be explained in further detail with reference to the followingexample embodiments, the under-nose support of the nasal mask interfaceis configured to extend within the mask cavity that receives the user'snose in use and has a contact surface that is configured to contact atleast a portion of the under-nose surface of the user's nose but withoutobstructing or completely obstructing the user's nostrils. Depending onthe size of the user's nose, the under-nose support contacts a portionor portions of the under-nose surface without any obstruction of theuser's nostrils as best case, or worst case only partially obstructs oneor both nostrils.

Various embodiments of the nasal mask interface and nasal seals of theinterface with the under-nose support will be described in thefollowing. It will be appreciated that such nasal seals can be employedor used with varying different nasal interface assemblies and headgearconfigurations but are particularly suited to headgear configurationsthat generate a resultant upward lift force in use that causes the nasalmask to slide or ride up the user's face such as, but not limited to,the above-ear headgear described and shown with reference to FIG. 2A.

Various embodiments of a nasal seal will be described, and in someembodiments with reference to an overall nasal mask interface assemblyincluding any one or more of a seal housing, conduit frame, headgearframe or yoke, and/or headgear. It will be appreciated that the variousembodiments of the nasal seal described may also be interchangeably usedin various suitable interface assemblies, and that the interfaceassembly examples and alternatives described in the context of oneembodiment are also applicable to other embodiments of the nasal sealsto be described. In general, it will be appreciated that the variouscomponents of the various embodiments may be interchanged and/orcombined with each other to form alternative configurations,

First Embodiment—Nasal Seal with Under-Nose Support Having a CentralExtension or Connecting Portion Overview

Referring to FIGS. 4-22 , a first form of e first embodiment of thenasal seal and a nasal seal interface assembly comprising the nasal sealwill be described in further detail. An alternative second form of thefirst embodiment nasal seal will also be described with reference toFIG. 23 .

Referring to FIGS. 4-10 , the first embodiment nasal mask interfaceassembly 100 comprises a flexible nasal seal 102 that is connected orconnectable to a rigid (or at least more rigid relative to the nasalseal) seal housing 104 to define a mask cavity generally indicated at106 that will receive the user's nose and a supply of gases for deliveryto the user's airway via their nares or nostrils as will be appreciatedby a skilled person. The rigid seal housing or shell 104 may either bedirectly connectable to headgear straps via one or more attachment orconnection points or assemblies provided on the seal housing oralternatively indirectly connectible to headgear via a headgear framecomponent 108 mounted or provided on the seal housing. In thisembodiment, the seal housing 104 is provided with an inlet opening oraperture 110 that is configured to connect to a flexible gases deliveryconduit 55 of the type previously described to deliver a heatedhumidified gases stream from a respiratory apparatus such as a CPAPdevice or similar. The seal housing 104 in this embodiment is alsoprovided with a collection of one or more apertures or holes in the formof an exhaust or bias-flow vent 112.

The flexible nasal seal 102 comprises a face-contacting surface 120having an inner peripheral edge 122 that defines a nose-receivingopening into the mask cavity 106 for receiving the user's nose in use.In use, the nasal mask interface 100 is secured against the user's faceusing headgear such that the contacting surface 120 of the nasal seal102 envelops or circumscribes the user's nose and sealingly engagesabout the user's nose such as against the cheek surfaces and/or lateralside surfaces of the user's nose, the upper lip region below the user'snose, and across the nasal bridge region of the user's nose. In thisembodiment, the nasal seal 102 also comprises an under-nose support 124that extends internally within the mask cavity 106 at a location orposition substantially rearward of or relative to the face-contactingsurface 120. The under-nose support 124 comprises a contacting surfacethat is configured or oriented to contact at least a portion of theunder-nose surface of the nose of the user when in use to at leastpartially counteract the upward lift resultant force R generated by theblow-off force B and headgear force A as previously described.

Referring to FIG. 10 , the top of the nasal mask interface is indicatedat 101 and the bottom at 103, the face-contacting side or wearer side ofthe nasal mask interface is indicated at 105 and the outer or exteriorside of the nasal seal is indicated at 107, for future reference. Theseal housing 104, headgear frame 108 and nasal seal 102 will each bedescribed in further detail in the following.

Seal Housing and Frame

Referring to FIGS. 11 and 12 , the seal housing or shell 104 is definedby an opening generally indicated at 140 that connects or couples to thenasal seal 102 on the wearer side of the nasal mask interface 100 andextends to the exterior or outer side of the nasal interface comprisingthe inlet 110 and exhaust vent 112 shown in FIG. 11 . The seal housing104 is a substantially hollow component that is generally shaped toprovide or define a cavity or volume indicated at 142 for receiving thegases stream from the inlet 110. The seal housing cavity 142 forms partof the overall mask cavity 106 when the seal housing 104 is assembled tothe nasal seal 102. In this embodiment, the seal housing 104 generallytapers inwardly in shape as it extends rearwardly from the opening 140to the exterior side.

In this embodiment, the exhaust vent 112 comprises collection orplurality of small holes or apertures that extend through the sealhousing and which collectively define a vent 112 in the central middleto upper region of the seal housing 104. It will be appreciated that inother embodiments, the vent or exhaust holes 112 may be omitted from theseal housing and could be provided at another location in therespiratory circuit, such as in a connecting conduit or swivel elbowcoupling the gases conduit to the inlet 110 of the nasal maskinginterface or elsewhere along the breathing circuit.

In this embodiment, the inlet aperture or port 110 is provided in thelower or bottom region of the seal housing 104 and is centrally located,although this location is not essential. It will be appreciated that theflexible gases conduit may be directly coupled via a connecting conduitto the inlet 110 or alternatively indirectly coupled via a straightconnector or conduit frame, connecting elbow such as a swivel elbow,ball joint connection or similar.

In this embodiment, the nasal seal 102 is removably or releasablycoupled or connectable to the seal housing 104 such that the nasal sealmay be removed for cleaning or replacement if required. In thisembodiment, the opening 140 of the seal housing 104 is provided with aperipheral ridge or extension that is configured to engage or receive acomplimentary peripheral channel provided on the outer side of the nasalseal 102 as will be explained later to thereby releasably couple thecomponents together. Once assembled, and secured to the user's nose, thenasal mask interface is substantially sealed and defines a substantiallyenclosed mask cavity 106.

In alternative embodiments, it will be appreciated that the nasal seal102 may be permanently or semi-permanently connected or coupled to theseal housing 104. By way of example, the outer side of the nasal seal102 distal to the face-contacting side may be over molded or otherwisesecured or adhered to or at the opening 140 of the seal housing 104 inalternative embodiments.

Whether the nasal seal 102 is removable or permanently coupled to theseal housing 104, it ill be appreciated that the edge or opening 140 ofthe seal housing is shaped and dimensioned to compliment or match thecorresponding outer side edge or connecting portion at the outer side ofthe nasal seal 102 about the periphery of the nasal seal interface.

The seal housing 104 may be formed with any suitable material thatprovides a rigid housing or which is at least rigid relative to theflexible nasal seal. In this embodiment, the seal housing is typicallyformed of a plastic polymer such as polycarbonate or similar. Inalternative embodiments, the seal housing may be semi-rigid. In oneexample, the seal housing may be formed from the same type of materialas the nasal seal (e.g. silicone material) but may be substantiallythicker so as to be generally less flexible or more rigid than the nasalseal.

With reference to FIG. 11 in particular, in this embodiment the nasalmask interface comprises a headgear frame component 108 in the form of ayoke that extends laterally about the exterior side of the seal housing104 between the vent 112 and inlet 110 from one side of the seal housingto the other. In this embodiment, the frame component 108 is removablyreceived within a complimentary channel formed into the surface of theseal housing 104 on the exterior side, although the frame mayalternatively be permanently fixed or coupled into the receivingchannel. As shown in FIG. 12 , the frame component 108 provides singleheadgear attachment points 144 on the left and right sides of the sealhousing 104. This provides a single connection point or location on eachside of the seal housing for connecting or coupling to a respectivesingle side strap of a headgear system, such as an above-ear headgearsystem as described with reference to FIG. 2A. In alternativeembodiments, it will be appreciated that the frame 108 may be omitted,and that the seal housing may provide headgear attachment points on eachside of the seal housing that are either integrally formed with the sealhousing or otherwise provided on the sides of the seat housing forconnecting to a headgear system such as the single side strap headgearsystem.

Nasal Seal

Referring to FIGS. 13-22 , the nasal seat component 102 of the nasalmask interface 100 of a first embodiment will be described in furtherdetail. The nasal seal 102 is flexible and soft, and may be formed of asilicone material or other suitable material.

Referring to the face-contacting or wearer side of the nasal seal 102shown in FIG. 13 , the contacting surface generally indicated at (120)is configured to seal about the user's nose, including across the bridgeof the user's nose. In this embodiment, the contacting surface 120circumscribes the nose and seals about the nose of the user. In thisembodiment, the contacting surface portion of the nasal seal comprisesan upper lip region generally indicated at 121 that is configured tocontact the upper lip region of the face of the user such as at alocation above the vermillion border and below the nares. The contactingsurface 120 also comprises left and right cheek or side regions 123 thatextend between the upper lip region 121 at the bottom of the seal 102and a region 125 corresponding to or proximal to the nasal bridge regionat the top of the seal 102. The cheek regions 123 of the contactingsurface 120 are configured to contact the medial cheek surface of theuser and/or lateral nose surface of the user on either side of the nose.The nasal bridge region 125 of the contacting surface 120 is configuredto extend over nose and contacts the nasal bridge region of the user'snose and connects the two cheek regions 123. The overall shape andconfiguration of the contacting surface 120 is configured to sealinglyconform to the contour of the user's face about the nose and tosealingly engage about the user's nose when secured to the user's headvia headgear and when the nasal mask interface receives flow of gases.The nasal seal 102 can be considered to be of the inflating type asunder pressure the seal urges the face-contacting surface 120 againstthe face of the user and deforms to substantially seal against thefacial contours of the user, including one or more of the upper lip, themedial cheek, the lateral nose and the bridge of the nose.

As previously discussed, the contacting surface 120 of the nasal seat102 terminates in an inner peripheral edge 122 that defines anose-receiving opening into the mask cavity when the seal 102 isassembled to the seal housing 104.

Referring to FIGS. 21 and 22 , the nasal seal 102 is substantiallydefined by the face-contacting surface portion 120 and a sidewallportion 126 that extends rearwardly from the contacting surface 120about the periphery of the seal and which terminates at a connectingedge generally indicated at 127 at the exterior or outer side of theseal that couples or is connectable to the opening 140 seal housing 104.As previously described, in this embodiment the nasal seal 102 isreleasably connectable to the seal housing and the terminating edge ofthe sidewall 126 comprises a peripheral channel 128 that is configuredto engage with a complimentary peripheral ridge or extension provided atthe opening 140 of the seal housing 104. As previously discussed, inalternative embodiments, the flexible nasal seal 102 may be permanentlyor semi-permanently connected or coupled to the seal housing 104 such asvia over molding, welding or other connecting methods. In furtheralternative embodiments, interface may be provided with a semi-rigid orrigid clip component that is shaped to correspond to the connecting edge127 on the exterior or outer side of the nasal seal. In suchembodiments, the connecting edge 127 of the seal may be overmolded orotherwise permanently connected to the rigid clip component, so as toprovide a rigid edge or portion at the outer side of the seal. The rigidclip component may be configured to engage or otherwise connect with acomplementary base or housing component to thereby couple the nasal sealto the base or housing.

As shown in FIG. 22 , the face-contacting surface 120 of the nasal sealforms a flange that curls or extends inward from the sidewall 126portion of the nasal seal. In this embodiment, the region at or towardthe terminating edge 127 of the sidewall 126 may be a thickened regionrelative to the remainder of the sidewall and contacting surfaceportions of the nasal seal, so as to accommodate the connecting channel128 or to otherwise provide some stability at the outerside to theoverall shape of the nasal seal.

As discussed, the nasal seal 102 is formed of a flexible and softmaterial such that nasal seal 102 is flexible relative to the rigidhousing 104. By way of example, the seal 102 may be formed of siliconematerial or similar.

Under-Nose Support of Nasal Seal

In this embodiment, the nasal seal 102 comprises an under-nose support124 (or nasal sling) that at least extends or is suspended laterallyacross the nasal seal between the sides of the seal and within the maskcavity 106 when the nasal seal 102 is assembled to the seal housing 104.The under-nose support 124 is configured to contact at least a portionof the under-nose surface of the user's nose so as to counteract anyresultant lift force created when the nasal mask is worn and in use aspreviously discussed.

In this embodiment, the under-nose support at least extends laterallyacross the nasal seal between the opposing left and right sides of thenasal seal. As shown, the under-nose support is disposed or locatedbehind or rearward of the nasal seal opening 106. The under-nose support124 is fixedly connected to the nasal seal in that it is not removable.In one form, the under-nose support 124 is integrally molded within thenasal seal. In alternative forms, it will be appreciated that theunder-nose support part or portion of the nasal seal 102 may be formedseparately and then fixedly coupled within the nasal seal such as via anadhesive or welding, or the like, or it could be connected to the sealhousing.

In this embodiment, the under-nose support configuration 124 comprisesan elongate main lateral portion or band 129 that extends across andwithin the nasal seal, such as suspended between opposing sides of theseal. With reference to FIGS. 14, 17 and 22 , the main lateral portion129 of the under-nose support is connected or extends from the nasalseal at locations isolated or displaced from at least the peripheralopening edge 122 of the contacting surface 120, but also in thisembodiment is entirely decoupled or displaced from the contactingsurface 120 such that the lateral portion 129 does not inhibit or reducethe sealing engagement or deformability of the contacting surface 120with the user's face in the cheek and/or lateral nose regions 123. Inthis embodiment, the main lateral portion 129 extends from or isconnected at locations 131 on the inner surfaces of opposing sidewall126 portions of the nasal seal rearwardly of the contacting surface 120.In this embodiment, the connecting locations 131 correspond with orinclude the terminating edge 127 of the sidewall 126, although this isnot essential.

In this embodiment, the under-nose support 124 further comprises acentral extension portion 132 that extends centrally from the mainlateral portion 129 and is coupled or connected to or at the openingedge 122 of the contacting surface 120 in the upper lip region 121. Inalternative embodiments, as will be explained later with reference toFIG. 23 , the central extension portion 132 may alternatively beconnected to a lower part of the upper lip region 121 of the contactingsurface 120 below the opening edge 122 of the seal, or alternatively maybe connected at a location at least partially or entirely displaced orisolated from the contacting surface 121, such as connected to a lowerpart of the sidewall 126 of the nasal seal that is rearward of thecontacting surface 120.

The under-nose support 124 comprising main lateral portion 129 andcentral extension portion 132 provides a contact surface that isconfigured and/or orientated to contact at least a part of theunder-nose surface of the user's nose in use. In this configuration, themain contact surface of the main lateral portion 129 is configured toengage with at least a portion of the tip of the under-nose surface ofthe user's nose, which may for example include the tip end of thecolumella 72 and portions of the alar rim 80 toward the tip of the nose(as shown in FIG. 3 ). The central extension portion 132 is configuredto contact the columella 72 region of the under-nose surface of theuser's nose, or at least a portion of the columella between the tip andbase of the nose, but preferably the majority of the columnellaextending from the base. The ultimate contact surface area of theunder-nose support depends on the shape and size of the user's nose. Theconfiguration of the under-nose support is designed to contact themaximum portion or portions of the under-nose surface withoutsubstantially obstructing the user's nostrils 74 which tend to bealigned with the open spaces 134 on either side of the central extensionportion 132 as shown in FIG. 13 . Depending on the size and shape of theuser's nose, the under-nose support 124 is generally configured to atbest completely avoid obstruction of the user's nostrils, but at worstonly partially obstruct one or both nostrils.

As shown, the contact surface of the under-nose support 124 is generallyoriented and configured relative to the nasal seal so as to engage theunder-nose surface of the user's nose. In this embodiment, the portionsof the under-nose support 124 are integral thin webs or strips of thenasal seal formed during molding of the seal. For example, the thicknessof the under-nose support transverse to its contact surface issignificantly smaller than the corresponding width of the contactingsurface at any location on the under-nose support. In one configuration,the thickness of the under-nose support portions may be substantiallysimilar to the thickness of the seal in the region of the contactingsurface 120 of the nasal seal.

In this embodiment, the width of the main lateral portion 129 of theunder-nose support 124 may vary along its length between the opposingsides of the nasal seal. In this example, the width W1 of the mainlateral portion 129 may progressively increase from the centre of thenasal seal toward each side. In this embodiment, the width W2 of thecentral extension portion 132 of the under-nose support 124progressively increases in width W2 as it extends from the main lateralportion 129 to the contacting surface 120. In alternative embodiments,it will be appreciated that the width of either or both of the mainlateral portions or central extension portions may be uniform alongtheir length, or have alternative width profiles along their length.

Referring to FIG. 22 , a central seal axis BB is defined as extendingtangentially between the outer uppermost and lowermost contact points atthe center of the contacting surface 120 when in a relaxed condition((e.g. not in use). As shown in FIG. 22 , at least a portion (e.g.indicated by axis CC extending coincident with the contact surface ofthe under-nose support portion(s) in the central region) of the contactsurface of the under-nose support 124 in a central region of theunder-nose support extends at an angle θ relative to seal axis BB suchthat the contact surface of the under-nose support is not parallel oraligned with the seal axis BB. In this embodiment, the contact surfacein the central region of the under-nose support 124 is oriented at anangle offset from the seal axis BB in the range of approximately 30 toapproximately 90 degrees, more preferably approximately 45 toapproximately 75 degrees, and more preferably approximately 60 degrees.This angular orientation of at least the main nose contacting portion orsurface of the under-nose support in the central region is configured tosubstantially align with the general or typical angular orientation ofthe under-nose surface of the user's nose when their nose is within thenasal seal.

As explained above, the under-nose support 124 in this embodiment isfixedly connected or is otherwise an integral component of the nasalseal 102. The accompanying drawings depict the nasal seal and itsunder-nose support 124 in a rest state, i.e. un-used. Like thecontacting surface 120 of the nasal seal, the under-nose support 124 isalso configured to be soft and flexible or pliable such that its shapeand position may conform with a sling-like effect to the under-nosesurface of the user's nose when the nasal mask interface is secured to auser's face in use or is otherwise worn. Typically, the under-nosesupport is non-stretchable in any direction, although may have a degreeof stretch in alternative embodiments.

Alternative Second Form—Central Extension Portion that is FullyDecoupled or Isolated from Opening Edge of the Nasal Seal

Referring to FIG. 23 , an alternative form of the nasal seal 102A of thefirst embodiment is shown. The nasal seal 102A is similar to the firstembodiment nasal seal 102 except it has a different under-nose supportconfiguration 124A that is fully decoupled or isolated from the edge ofthe face-contacting surface 120 of the nasal seal. Like numeralsrepresent like components. The alternative under-nose supportconfiguration 124A comprises a main lateral proportion 129 and a centralextension portion 132A. The difference relative to nasal seal 102 isthat the central extension portion 132A does not couple or connect tothe edge 122 of the contacting surface 120 but rather to a lower part ofthe contacting surface in the upper lip region or alternatively to apart of the lower region of the seal that is not part of the contactingsurface 120, such as a part of the lower sidewall 126 of the nasal seat.In this configuration, the under-nose support 124A is fully decoupledfrom the edge 122 of the contacting surface 120, and in someconfiguration is completely decoupled from the contacting surface 120altogether such that the main lateral portion 129 and central extensionportion 132A connect to respective sidewall portions of the nasal sealat locations displaced from or adjacent to the contact contactingsurface 120 that engages the user's face. The alternative embodiment ofthe nasal seal 102A is otherwise similar in function and configurationas nasal seal 102 and may be coupled to the seal housing 104 to form thenasal seal interface assembly as with the first embodiment nasal seal102.

Second Embodiment—Nasal Seal with Under-Nose Support Having SideExtension Portions

Referring to FIGS. 24-29 , various forms of a second embodiment of thenasal mask interface will be described. The nasal mask interface of thesecond embodiment is substantially similar to the first embodiment,except in a first form comprises a nasal seal 102B that has analternative under-nose support configuration 124B. The nasal seal 102 isotherwise similar to the first embodiment nasal seal 102 and can becoupled to a seal housing 104 to form the nasal seal interface assemblyas previously described. Like reference numerals represent likefeatures.

In this first form of the second embodiment, the alternative under-nosesupport configuration 124B still comprises a main lateral portion 129extending across within the nasal seal between opposing sides of thenasal seal and rearwardly of the contacting surface 120. A centralextension portion is not provided as in the first embodimentconfiguration. Rather, the under-nose support 124B comprises left andright side extension portions 132B that extend from opposing sides ofthe main lateral portion 129 and each connecting to the lower openingedge 122 of the contacting surface 120 at respective locations towardthe sides of the seal in the upper lip region 121 of the contactingsurface 120. In this embodiment, the under-nose support 124B may alsocomprise a lateral extension 135 that extends along or adjacent thelower opening edge 122 of the contacting surface 120 between the sideextension portions 132B. Alternatively, lateral extension 135 may beconsidered as an extension of contact surface 120 in the upper lipregion to which the side extension portions 132B connect to. It will beappreciated that the lateral extension portion 135 could omitted inalternative embodiments such that the side extension portions 132B mayextend down to connect directly to the edge 122 of the contactingsurface 120 without a lateral extension portion 135.

In this alternative configuration 124B, the main lateral on 129 is againconfigured to substantially contact a portion of the columella 72 of theuser's under-nose surface such as at or toward the tip of the user'snose and end portions of the alar rim 80 at the tip of the nose. Theside extension portions 132B are each configured for substantialalignment and contact with respective portions of the alar rims 80 ofthe under-nose surface, such as including portions of the alar rimextending from the base of the nose. This configuration therefore leavesa main opening 134B in the under-nose support between the main lateralportion 129, side extension portions 132B, and contacting surface 120 inthe upper lip region, for the user's nostrils 74.

Alternative Second Form—Side Extension Portions that are Fully Decoupledor Isolated from Opening Edge of the Nasal Seal

Referring to FIG. 29 , an alternative second form of the nasal seal 102Cof the second embodiment is shown. Like numerals representing likefeatures. Again, this nasal seal 102C is otherwise similar to the secondembodiment nasal seal but with an alternative under-nose supportconfiguration 124C in which the side extension portions 132C extend fromthe main lateral portion 129 and connect to a portion of the nasal sealin the upper lip region that is displaced or isolated from edge 122 ofthe nasal seal such that the side extension portions 132C are decoupledfrom the edge 122 of the nasal seal. In one configuration, the sideextension portions 132C connect or extend to a portion of the contactsurface 120 below the edge in the upper lip region, or in an alternativeconfiguration connect to the nasal seal at locations displaced from thecontact surface 120 entirely, such as connecting to the respectivelocations on the sidewall of the seal in the upper lip region below thelower edge 122 of the opening. This configuration provides an under-nosesupport 1240 that is decoupled from the edge 122 of the contactingsurface 120 of the nasal seal.

Third Embodiment—Nasal Seal with a ‘Floating’ Under-Nose Support

Referring to FIGS. 30-34 , a third embodiment of the nasal seal 102Dwill be explained. As with the previous embodiments, the nasal seal 102Dis similar to the first embodiment nasal seal 102 in that it may be usedin a nasal mask interface assembly as previously described, for example,by being coupled or connected to a seal housing 104. Like referencenumerals represent like features.

The third embodiment nasal seal 102D comprises an alternative under-nosesupport 124D that consists only of the main lateral portion or band 129without any central or side extension portions. In particular, theunder-nose support 124D comprises an elongated strip or band of materialthat extends laterally across the nasal seal between opposing sides ofthe seal and which extends or is located rearwardly of the face contactsurface 120, as in the previous embodiments. As with the previousembodiments, the lateral band 129 may be coupled or connected at eachend to a respective portion of the sidewall 126 or other portion of theseal such that the under-nose support is decoupled or isolated from thecontacting surface 120, or at least the edge of the contacting surface.Without the central or side extension portions of the previousembodiments, the under-nose support 124D can be considered as a‘floating’ support that has a greater degree of movability within theseal.

In this configuration, the under-nose seal 124D has less contact surfacearea and therefore contacts less of the under-nose surface of the noseof the user. In particular, without any of the central or side extensionportions, less of the under-nose surface tends to be contacted by thefloating under-nose support configuration 124D. The floating under-nosesupport tends to engage or contact the columella and portions of theadjacent alar rims 80 at or toward the tip of the nose, depending on thesize of the user's nose. For those with larger noses, the under-nosesupport may contact in the middle region of the under-nose surface orfurther toward the under-nose surface at the base of the nose.

Fourth Embodiment—Low-Profile Nasal Mask Interface Overview

A fourth embodiment nasal mask assembly will now be described withreference to FIGS. 35-102 .

With reference to FIGS. 35 and 36 , the fourth embodiment nasal maskassembly comprises a nasal mask interface 200 that is secured to auser's head via headgear 250 and the nasal mask interface 200 isconnected to a flexible gases supply conduit 260, which in use deliversa supply of breathable gas to the nasal mask interface 200 for deliveryto the user's airways via their nose. In this embodiment, the headgear250 comprises side or front straps 252 that connect to opposing sides ofthe nasal mask interface 200 at attachment points 256 and which extendalong the sides or cheeks of the user's face and over the user's ears.The pair of front or side straps 252 connect to or integrally extendinto one or more other straps or strap portions. In this embodiment, theheadgear 250 comprises a top or crown strap 254 that extends over theuser's head or crown, and a back or rear strap 258 that extends aroundthe back of the user's head. The side straps 252 are integrally formedor otherwise connected to the top 254 and back 258 straps as will beappreciated by a skilled person. As with the previous embodiments, theheadgear straps are typically formed of or comprise a flexiblebreathable material such as Breath-o-Prene®, a breathable neoprenematerial, or neoprene material or similar. Further aspects of theheadgear configuration and its attachment and interaction with the nasalmask interface 200 will be explained later. In this embodiment, theheadgear may have automatic adjustment capability or mechanisms, as willbe further described, although these are not essential to allembodiments.

Referring to FIGS. 37-46 in particular, the nasal mask interface 200comprises a flexible nasal seal 202 that is either permanently orreleasably connected or mounted to a complementary seal housing 204. Theseal housing 204 is typically formed of a rigid material or is at leastmore rigid than the flexible nasal seal 202. As with the previousembodiments, the nasal seal 202 and seal housing 204 togethercollectively define or form a mask cavity or volume that is configuredto receive at least a portion of the user's nose in use and whichreceives a supply of a breathable gas from the gases supply conduit 260.In this embodiment, the gases supply conduit 260 is releasably connectedto the seal housing 204 although it will be appreciated that inalternative embodiments the conduit may be permanently or integrallyconnected into the seal housing 204, In this embodiment, the nasal maskinterface 200 comprises a conduit frame 211 that is either permanentlyor releasably connected to an end of a gases supply conduit. The conduitframe 211 in this embodiment is releasably connectable to acomplementary central air aperture or inlet 210 provided in the sealhousing to thereby connect the supply conduit 260 to the nasal maskinterface 200.

In this embodiment, a headgear frame in the form of a yoke 208 isreleasably connected to the outer side surface of the seal housing 204.The yoke 208 is generally curved (outer front surface being convex, andinner surface engaging with seal housing being concave) in shape anextends laterally across the seal housing 204 and at each end extends ina direction toward the face-contacting side of the nasal mask interfacebut outwardly away from the lateral sides of the nasal seal 202. Eachdistal end of the yoke 208 connects to a respective end of one of theside straps 252 of the headgear 250 such that the headgear 250 has asingle attachment point on each side of the nasal mask interface 200. Inthis embodiment, the headgear may be permanently or non-releasablyconnected to the yoke 208. The yoke may be releasably connected to theseal housing 204 such that the yoke 208 and headgear 250 may be removedor released from the seal housing if desired.

In this embodiment, the nasal mask interface 200 is provided with one ormore bias flow outlet or vents 212 for providing gas washout from thenasal mask interface 200. In this embodiment, the bias flow ventcomprises an arrangement of small apertures or holes extending throughthe seal housing 204. The vent arrangement comprises one or more arraysof apertures at particular locations on the seal housing as will beexplained in further detail. As with the previous embodiments, the nasalseal 202 is provided with an under nose support 224 that extends or issuspended laterally across the nasal seal within the mask cavity andwhich is configured to contact at least a portion of the under-nosesurface of the user's nose so as to counteract any result in lift forcecreated with the nasal mask is worn and in use as previously discussed.

Further details and aspects of the various components of the nasal maskinterface 200 will now be described.

General Shape and Configurations Aspects

Referring to FIG. 42 , in this embodiment the orientation or angle ofthe yoke 208 and conduit frame 211 are offset relative to each other.For example, the longitudinal axis of the conduit frame 211 representedby line AE is angled with respect to the longitudinal axis or planeextending through or defining the yoke 208 represented by line AF. Inthis embodiment, the angle between the longitudinal axis AE of theconduit frame 211 and longitudinal axis AF of the yoke 208 when viewedfrom the side of the nasal mask interface 200 is preferably in the rangeof approximately 20° to approximately 60°, more preferably approximately30° to approximately 50°, even more preferably approximately 35° toapproximately 45°, and even more preferably approximately 38°. In thisexample, the longitudinal axis NE of the conduit frame 211 andlongitudinal axis AF of the yoke 208 are defined relative to a sideelevation view of the nasal mask interface 200 by way of explanationonly. In some embodiments, this angular offset between the conduit frameand yoke may assist in directing the gases supply conduit away from theuser, and also may assist in reducing hose drag.

Referring to FIG. 44 , the conduit frame 211, seal housing 204, nasalseal 202, and yoke 208 all generally exhibit a substantially concavecurvature (on their face facing surfaces) that generally follows thecurvature of a user's face and assists in the nasal mask interfaceconforming to the user's face about their nose. In this embodiment, ascan be seen from the top view in FIG. 44 , the radius of curvature ofthe yoke 208 (at least in the lateral side portions) is generally largerthan that of the conduit frame 211 and/or seal housing 204 as the yokeis not intended to contact the user's face and is configured to extendat an angle away from the outer wall of the nasal seal 202 that extendsbetween the face-contacting surface of the nasal seal and the outer sideof the nasal seal that connects to the seal housing 204.

Referring to FIG. 43 , the nasal aperture or nose-receiving opening 206on the face-contacting side of the nasal seal 202 is shown. The pair ofsingle headgear attachment or connection points 272 on each side of thenasal mask interface are shown at 272 at each distal end of the yoke208. In this embodiment the headgear connection points 272 are locatedon each lateral side of the nasal mask interface 200 at locations on theyoke 208 that are most distal from the centre of the nasal maskinterface. The under-nose support 224 can be seen through the nasalaperture 206 and extends within the mask cavity provided by the nasalseal 202 and seal housing 204. In this embodiment, the under-nosesupport 224 has three connection points to the nasal seal 202. As willbe explained in detail later, the under-nose support 224 comprises aconnection point toward each upper inner lateral side or surface of thenasal seal, and a third connection point at or toward the centre bottomof the nasal seal. In this embodiment, the third connection is to thecenter bottom edge of the nasal aperture 206.

Referring to FIGS. 42 and 44 , some main outer dimensions of the overallprofile of the nasal mask interface 200 in this embodiment will bedescribed by way of example only to provide a sense of scale. In thisembodiment, the ratio of the overall height to the overall depth of theseal housing 204 and nasal seal 202 assembly is in the range ofapproximately 1:0.8 to approximately 1:1.2, and in this exampleembodiment the overall height is substantially equal to the overalldepth of the seal housing and nasal seal assembly, i.e. a ratio ofapproximately 1:1. In this embodiment, the overall lateral width of theseal housing and nasal seal assembly is greater than the overall heightand depth of the assembly. In this embodiment, the ratio of the overallheight to overall depth to overall lateral width of the seal housing andnasal seal assembly is in the range of approximately 1:0.8:1 toapproximately 1:1.2:1.4, and approximately 1:1:1.2 in this exampleembodiment

By way of example only, example dimensions of one example configurationof the nasal mask interface will be set out with reference to FIGS. 42and 44 . In this example, the overall height of the seal housing 204 andnasal seal 202 assembly from the top to the bottom as indicated at 282is in the range of approximately 27 mm to approximately 67 mm, andpreferably approximately 47 mm. The overall height of the seal housing204, nasal seal and installed conduit frame 211 as indicated at 274 isin the range of approximately 30 mm to approximately 70 mm, andpreferably approximately 50 mm. The overall depth of the seal housing204 and nasal seal 202 assembly as indicated at 276 is in the range ofapproximately 41 mm to approximately 66 mm, and preferably approximately46 mm, and the overall depth of the seal housing 204, nasal seal 202 andinstalled conduit frame 211 as indicated at 278 is in the range ofapproximately 5 mm to approximately 76 mm, and preferably approximately56 mm. The lateral width of the seal housing 204 and nasal seal 202assembly (see FIG. 44 ) as indicated at 280 is in the range ofapproximately 52 mm to approximately 77 mm, and preferably approximately57 mm.

Nasal Seal

Referring to FIGS. 47-67 , the nasal seal 202 of the nasal maskinterface 200 will be described in further detail. The nasal seal 202 isflexible and soft, and may be formed of a silicone material or othersuitable material as will be appreciated by a skilled person.

Referring to the face-contacting or wearer side of the nasal seal 202shown in FIG. 47 , the contacting surface is generally indicated at 220and is configured to seal about the user's nose, including across thebridge of the user's nose. In this embodiment, the contacting surface220 circumscribes at least a portion of the nose and seals about thatportion of the nose of the user. The contacting surface 220 of the nasalseal comprises an upper lip region generally indicated at 221 that isconfigured to contact the upper lip region of the face of the user suchas at a location above the vermillion border and below the nares. Thecontacting surface 220 also comprises left and right cheek or sideregions 223 that extend between the upper lip region 221 at the bottomof the seal and an upper region 225 corresponding to or proximal to thenasal bridge region at the top of the nasal seal 202. The cheek regions223 of the contacting surface 220 are configured to contact the medialcheek surface of the user and/or lateral nose surface of the user oneither side of the nose. The nasal bridge region 225 of the contactingsurface 220 is configured to extend over the nose and contacts the nasalbridge region of the user's nose, and connects to the two cheek regions223. As will be explained in further detail later, in this embodimentthe nasal seal 202 comprises a lower profile height dimension thanconventional nasal masks such that the nasal bridge region 225 of thecontacting surface is configured to contact the user's nasal bridge in amiddle region of the nasal bridge at a location on the nasal bridgebetween the lower tip of the user's nose and the upper extremity of thenasal bridge between the user's eyes. In this embodiment, the nasalbridge region 225 of the contacting surface 220 is configured to contactthe user's nasal bridge in a region of the nasal bridge that is belowthe user's eyes. In an embodiment, the nasal bridge region 225 of thenasal seal is configured to contact the user's nasal bridge in theregion defined between the nares of the nose and the center of the nasalbridge. In an embodiment, the nasal bridge region 225 of the nasal sealis configured to contact the bottom half of the user's nose.

Referring to FIG. 52 , in this embodiment the nasal bridge region 225 ofthe contacting surface 220 comprises a central valley region or portionindicated at 245 that is recessed relative to the remainder of thecontacting surface. The valley region 245 is configured to engage withthe user's nasal bridge and is shaped to conform substantially to thenasal bridge of a user.

The overall shape and configuration of the contacting surface 220 isarranged to sealingly conform to the contour of the user's face aboutthe nose and to sealingly engage about the user's nose when secured tothe user's head via headgear and when the nasal mask interface receivesa flow of gases. In this embodiment, the nasal seal can be considered tobe of the inflating type as under pressure the seal urges theface-contacting surface 220 against the face of the user and deforms tosubstantially seal against the facial contours of the user, includingone or more of the upper lip, the medial cheek, the lateral nose and thebridge of the nose.

The contacting surface 220 of the nasal seal 202 terminates at an innerperipheral edge 222 that defines the nose-receiving opening or nasalaperture 206 into the mask cavity. The mask cavity is defined or formedwhen the nasal seal 202 is assembled or connected to the seal housing204. Referring to FIG. 48 , the outer side of the nasal seal opposite tothe face-contacting side of FIG. 47 is shown. The outer side of thenasal seal 202 connects to the seal housing 204. In this embodiment, theouter side of the nasal seal 202 terminates at a connecting edge 227that defines an outer side or housing aperture 228 for receiving orconnecting with the seal housing 204.

Referring to FIG. 51 , the connecting edge 227 at the outer side of thenasal seal 202 is not coincident with a single plane or extends in asingle plane. Referring to FIGS. 48 and 51 , in this embodiment theconnecting edge 227 at the outer side of the nasal seal comprises anupper edge 227A, a lower edge 227B and lateral side edges 227C, 227Dthat extend between the upper 227A and lower 227B edges. In thisembodiment, the upper edge 227A protrudes rearwardly of the side lateraledges 227C and 227D. At least a central portion of the lower edge 227Bmay also protrude rearwardly of the lateral edges 227. In thisembodiment, at least a central portion of the upper connecting edge 227Aprotrudes rearwardly beyond both the lateral edges 227C, 227D and thelower edge 227B. As shown in FIG. 53 , the upper edge 227A protrudes orbulges outwardly to an apex at a centre of the nasal seal.

In this embodiment, the nasal aperture 206 formed on the face-contactingside of the nasal seal 202 is generally or semi triangular in shape tomatch the natural geometry of a human nose. The housing aperture 228 onthe outer side of the nasal seal 202 is generally or semi rectangular inshape.

Referring to FIGS. 47 and 48 , the under-nose support 224 can be seenand is generally concave or U-shaped with three connection or attachmentpoints to or within the nasal seal 202. As shown, the under-nose support224 is suspended like a sling or hammock between two upper connectionpoints 231 located at opposing upper lateral positions or surfaceswithin the nasal seal 202. In particular, the upper lateral connections231 are located on the inside surface of the nasal seal 202, one on eachside of the central apex region of the nasal aperture 206. In thisembodiment, the lateral connections 231 of the under-nose support 224are configured or arranged in a vertical orientation such that the inneror contact surfaces of the under-nose support 224 substantially face oroppose each other at or toward the lateral connection points 231. Inparticular, the lateral contact surfaces of the under-nose support 224may be substantially parallel to each other at or toward the lateralconnection points 231. The under-nose support 224 in this embodimentfurther comprises a third connection at or toward the centre bottom ofthe nasal seal. In this embodiment, the bottom centre connection point232 couples to or at the centre bottom region of the edge 222 of thecontacting surface 220 of the nasal seal that defines the nasal aperture206. The under-nose support 224 and its connections will be explainedfurther in detail later.

Referring to FIGS. 51-53 , the nasal seal to 202 is substantiallydefined by the face-contacting surface portion 220 (shown in FIG. 47 )and a sidewall portion 226 (shown in FIG. 51 ) that extends rearwardlyfrom the contacting surface about the periphery of the seal and whichterminates at the connecting edge 227 at the exterior or outer side ofthe seal that couples or is connected to the seal housing 204. In thisembodiment, the nasal seal 202 may comprise varying thickness profilesor regions extending from the nasal aperture edge 222 on theface-contacting side of the nasal seal to the connecting edge 227 at theouter side of the nasal seal.

In this embodiment, the nasal seal 202 comprises at least a first frontregion generally indicated at 233 that extends from the nasal apertureedge 222 to an intermediate peripheral boundary 235 located on the sidewall portion 226 and a second rear region 234 that extends from theintermediate peripheral transition boundary 235 to the connecting edge227 on the outer side of the seal.

In this embodiment, the front region 233 includes the contacting surface220 and at least a portion of the side wall portion 226 of the nasalseal adjacently contact surface 220, The rear region 234 comprises theremainder of the side wall portion 226 extending back from thetransition boundary 235 to the connecting edge 227.

Referring to FIG. 56 , in this embodiment the front region 233 of thenasal seal comprising the contact surface is thinner or of reducedthickness on average relative to the rear region 234 of the nasal seal.In this embodiment, the nasal seal further comprises an additional thirdthickness region 236 within the front region 233. In particular, thefront region 233 transitions into a thinner edge region 236 adjacent thenasal aperture edge 222. The edge region 236 is thinner than theremaining portion of the front region 233. In this embodiment, the edgeregion 236 is a minor portion of the front region 233.

The described thickness profile provides the nasal seal 202 withstability and enhances the sealing engagement with the user's nose. Inparticular, the thicker rear region 234 provides stability to theoverall nasal seat shape, while the reduced thickness of the frontregion 233 comprising the contacting surface 220 encourages conformityof the nasal seal with the user's nose. Furthermore, the edge region 236about the periphery of the nasal aperture edge 222 is the thinnest partof the contacting surface 220 and provides increased user comfort andsealing conformity. It will be appreciated that the thicknesses of therear region 234, front region 233 and edge region 236 may be uniformwithin the respective regions or may have varying thicknesses within theregions. For example, in this embodiment, the rear region 234 graduallyreduces in thickness from the contacting edge 227 to the intermediatetransition boundary 235. The front region 233 is of substantiallyuniform thickness in the majority portion and the minor thinned edgeportion 236, with the edge portion 236 having a uniform thicknessesreduced relative to the majority of the front region. In thisembodiment, the majority portion of the front region 233 transitionsgradually to the thinner edge region 236 as shown at the body transitionzone 237 in FIG. 56 . As shown in FIG. 56 , the face-contacting surface220 of the nasal seal forms a flange that curls or extends inward fromthe side wall portion 226 of the nasal seal, the flange including thethinned edge portion 236.

Under-Nose Support of Nasal Seal

In this embodiment, the under-nose support 224 of the nasal seal 202 isin the form of a nasal sling or hammock that at least extends or issuspended laterally across a central portion of the nasal seal withinthe mask cavity. The under-nose support 224 is configured to contact atleast a portion of the under-nose surface of the user's nose so is tocounteract any resultant lift force created when the nasal mask is wornand in use with pressurised gases flowing as previously discussed.

In this embodiment, the under-nose support 224 is entirely defined orenclosed within the outer envelope of the nasal seal, i.e. it does notprotrude or extend beyond the connecting edge 227 on the outer side ofthe nasal seal that connects to the seal housing or the contactingsurface edge 222 of the nasal aperture 206. However, it will beappreciated that at least a portion of the under-nose support 224 mayprotrude beyond the housing aperture defined by the connecting edge 227in alternative embodiments.

In this embodiment, the under-nose support 224 is suspended laterallyacross a central region of the nasal seal 202 between left and rightsides of the nasal seal. As shown, the under-nose support is disposed orlocated behind or rearward of the nasal aperture or opening 206 on theface-contacting side of the nasal seal. The under-nose support 224 isfixedly connected to the nasal seal in that it is not removable in thisembodiment. In one form, the under-nose support is integrally mouldedwithin the nasal seal. In alternative forms, the under-nose support partor portion of the nasal seal may be formed separately and then fixedlycoupled within the nasal seal via adhesive or welding or the like, or itcould be connected to the seal housing.

In this embodiment, the under-nose support configuration 224 comprisesan elongate main lateral portion or band 229 that extends laterallyacross at least a portion of the nasal seal and within the nasal seal.With reference to FIGS. 47-49, and 54-56, and 57 , in this embodimentthe main lateral portion 229 of the under-nose support 224 is suspendedor connected at each opposite end to a respective upper connection point231 located on the upper internal surface of the nasal seal on oppositesides of the seal relative to the apex region of the nasal aperture 206.In this embodiment, the distal ends of the main lateral portion 229 ofthe under-nose support 224 are connected to the inner surface of thenasal seal via respective reinforcing portions or regions, for examplein the form of ribs 241. In this embodiment, the ribs 241 extend in asubstantially vertical orientation from the upper lateral positionswithin the nasal seal inner surface and extend into or connect to arespective distal end of the main lateral portion 229 at connectionlocations 231. In this embodiment, the ribs 241 are integrally mouldedwith the main lateral portion 229 of the under-nose support 224. It willalso be appreciated that the ribs 241 at the ends of the main lateralportion 229 can be considered to be part of the under-nose support andmain lateral portion 229. In other words, the reinforcing portions orregions 241 may be considered as extension portions of the main lateralportion, or simply end portions of the main lateral portions.Alternatively, the reinforcing portions or regions may be considered tobe separate components or formations that are connected or integrallyformed with the ends of the main lateral portions. The functionality andeffect of the reinforcing portions or ribs 241 remains substantially thesame under either interpretation.

Referring to FIG. 55 , the rib 241 is at a portion of its peripheraledge coupled to or extends from a region of the inner surface of thenasal seal comprising a portion of the rear region 234 and front region233. In this embodiment, the ribs extend across a portion of the rearregion 234 and the majority of the front region 233 comprising thecontact surface, but excluding the thinned edge region 236 adjacent thenasal aperture. However, it will be appreciated that in alternativeembodiments the ribs 241 may also extend from or contact or extend intoat least a portion of the thinned edge region 236. In this embodiment,the main lateral portion 229 of the under-nose support connects to eachrespective rib 241 at a portion of the rib that extends or is coincidentwith the thicker rear region 234 of the nasal seal wall. The ribs 241provide the main lateral portion 229 of the under-nose support 224 witha solid connection within the nasal seal and also provide the dualfunction of structural support to the nasal seal by increasing therigidity in that area or region of the nasal seal that contacts thepatient on either side of the nose. In particular, the ribs 241 flank orare located either side of the upper valley region 245 of the contactingsurface 220 (see FIG. 52 ) associated with the nasal bridge region ofthe contacting surface 220. In particular the ribs or panels 241preventing the nasal seal from collapsing under excessive compressionforce while also allowing for a secure connection between the under-nosesupport and the inside surface of the nasal seal.

In some embodiments, the ribs may also function, either directly orindirectly, to give feedback to the user when the mask is overtightened.As described further below, the buckling of the ribs may be configuredto deform or change the shape of the under-nose support to squeeze uponthe user's nose, and/or to cause portions of the contacting surfaceadjacent or associated with the ribs to progressively press tighter intothe side of the nose under increased compression of the nasal seal, e.g.due to tightening of the headgear.

Referring to FIG. 55 , in this embodiment, a recessed region or zone 243is provided or formed between the front portion 242 a of the rib 241 andthe rear portion 242 b that connects to the main lateral portion 229 ofthe under-nose support 224. This recessed region 243 creates a bucklingzone or axis 242 in each rib 241. In this embodiment, the buckling axis242 extends from between toward the thickness region transition boundary235 and the apex of the recessed region 243.

In some configurations, the buckling axis 242 enables the rib 241 tobuckle outwardly toward its adjacent inner surface of its associatedlateral wall of the nasal seal in use when the nasal seal is compressedin its depth dimension when worn by a user. This buckling of the ribsallows the front regions 242 a of the ribs 241 to bend or compressinwardly toward the user's nose to enhance the seal created in use, andmay also lift the under-nose support into the under-nose surface of theuser.

In other configurations, the buckling axis 242 enables the ribs 241 tobuckle inwardly toward each other in use when the nasal seal iscompressed in its depth dimension when worn by a user. This inwardsbuckling of the ribs causes the under-nose support 224 to tighten orclose-up at least in a lateral width direction and this acts to causethe under-nose support squeeze on or tighten onto the surface of theuser's nose. In other words, the inwards buckling of the ribs causes thecontact surfaces of the lateral regions of the main lateral portion ofthe under-nose support to move toward each other to effectively narrowor tighten the U-shape of the under-nose support so as to squeeze uponthe user's nose.

The recessed region 243 can also be a region or zone of the rib 241 thathas reduced depth (i.e. distance of the free peripheral edge of the ribfrom the edge of the rib connected to the inner surface of the seal) orsurface area relative to other portions of the rib.

Referring to FIG. 48 , in this embodiment the upper connecting locations231 of the under-nose support are located in bound of the lateralextremities or sides of the nasal seal. In particular, the verticalconnecting ribs 241 and connection points 231 are offset relative to theouter lateral width of the nasal seal on their respective sides. In thisembodiment, the distance between the connection locations 231 isgenerally equal to or less than the outermost width of the nasalaperture indicated at 242A in FIGS. 47 and 48 , in particular, theconnection points 231 of the main lateral portion 229 of the under-nosesupport are located within the same width zone as the nasal aperture 206in the context of the nasal seal. In this embodiment, the connectingribs 241 extend from the contacting surface 220 in the upper lateralcheek regions 223 of the contacting surface at a location that engageswith the cheek and/or outer nose or lateral nose surface of a userrelative to their nasal bridge.

In some embodiment, referring to FIG. 57 , the main lateral portion 229of the under-nose support 224 is arranged to extend laterally across thenasal seal 202 at a depth that is approximately midway or in the centreof the overall depth profile of the nasal seal in the dimensionextending from the contacting surface 220 to the outermost portion ofthe connecting edge 227 on the outer side of the nasal seal. However; inalternative embodiments the main lateral portion may be arranged toextend laterally across the nasal seal at other depths, whether closeror further from the contacting surface, and may also have portions thatextend or protrude beyond the outer side connecting edge 227 or mainenvelope of the nasal seal.

In this embodiment, the under-nose support 224 also comprises a thirdconnection to nasal seal in addition to the two upper lateralconnections 231. In this embodiment, the under-nose support is connectedto a central lower or bottom portion of the nasal seal as indicated at232. In this embodiment, the lower central connection of the under-nosesupport 224 is in the form of a central extension or connecting portion232 that extends centrally from the main lateral portion 229 and iscoupled or connected to or at the nasal aperture edge 222 of thecontacting surface 220 in the upper lip region 221 of the nasal seal. Inthis embodiment, the central connecting portion 232 has an approximatelyhour glass width profile. In particular, the width dimension of thecentral connecting portion 232 at both the nasal aperture edge 222 andthe interface with the main lateral hand 229 is larger than a widthdimension of the central connecting portion 232 in a middle or intomediate region. For example, the central connecting portion 232 is anelongate portion that extends from a first end 232A that is coupled orintegrally formed with the nasal aperture edge 222 of the contactingsurface 220 to a second end 232B that is coupled or integrally formed tothe main lateral band 229 of the under-nose support 224 (see FIGS. 48,49 and 54 ). In this embodiment, the width dimension of the centralconnecting portion 232 progressively reduces from each of its ends 232A,232B toward a central or middle region of reduced width to provide anapproximately hourglass width dimension profile.

Referring to FIGS. 55 and 56 , the central connecting portion 232 of theunder-nose support comprises a varying thickness profile in thedirection transverse to the contacting surface of the connection portion232. In this embodiment, the thickness of the central connecting portion232 tapes or reduces in width from its second end 232B at the mainlateral portion 229 to its first end 232A at the nasal aperture edge222. For example, the thickness of the central connecting portion 232 atthe second end 232B is substantially equal or uniform with the thicknessof the main lateral portion or band 229 in that region, and thethickness tapers or reduces either from the second end 232B or at apoint in the middle region of the connecting portion 232 to a reducedthickness at the first end 232A at the nasal aperture edge 222. In thisembodiment, the reduced thickness at the first end 232A is substantiallyequal to or uniform with the thickness of the nasal aperture edge 222 ofthe contacting surface. For example, the thickness of the centralconnecting portion 232 at its first end 232A may be substantially equalto the thickness of the thinned edge region 236 of the contactingsurface 220 of the nasal seal.

Referring to FIGS. 47-49 and 54 in particular, in this embodiment theunder-nose support 224 is configured with a curved profile across thelateral width of the under-nose support between the upper lateralconnections 231. The curvature profile may vary across the lateral widthof the under-nose support in some embodiments, but alternatively it mayhave a uniform curvature in other embodiments. In the embodiment shown,the curvature profile varies. In this embodiment, the contacting surfaceof the main lateral portion 229 of the under-nose support 224 has asteeper curved profile in a middle or central region 235 relative to aflatter curved profile in the remaining lateral or outer regions 236that extend to the upper lateral connections 231. For example, in thecentral region indicated at 235 the main lateral portion 229 is providedwith a first radius of curvature that is substantially uniform in thecentral region 235. The radius of curvature of the remaining lateralregions 236 on either side of the central region 235 may be constant orvarying, but generally has a radius of curvature that is larger than thefirst radius of curvature of the central region 235 such that it isgenerally of flatter curvature. In this embodiment, the main lateralportion 229 is or comprises a curved contact surface profile across itsentire lateral width without any flat regions.

In this embodiment, the width of the contacting surface of the mainlateral portion 229 of the under-nose support 224 may vary along itslength between the opposing sides of the nasal seal. In this embodiment,the main lateral portion 229 comprises a substantially uniform widthindicated at 238 (see Figure A15) in the central region 235, with thewidth then progressively increasing in the outer lateral regions 236toward the connection points 231.

Referring to FIG. 56 , a central seal axis AG is defined as extendingtangentially between the outermost upper and lower contact points of thecentral region of the contacting surface 220 when the nasal seal is in arelaxed condition (e.g. not in use). As shown in FIG. 56 , at least aportion of the contact surface of the under-nose support in a centralregion is indicated by axis AH extends at an angle defined or indicatedat 239 relative to the seal axis AG such that the contact surface of theunder-nose support is not parallel or aligned with the seal axis AG. Inthis embodiment, the contact surface in the central region of theunder-nose support 224 is oriented at an angle offset from the seal axisAG in a range of approximately 40° to approximately 80°, more preferablyapproximately 45° to approximately 75°, even more preferablyapproximately 50° to approximately 70°, even more preferablyapproximately 55° to approximately 65°. As shown, at least a portion ofthe central connecting portion 232 also has a corresponding or alignedangular offset.

As explained above, the under-nose support 224 in this embodiment isfixedly connected or otherwise an integral component of the nasal seal202. The drawings depict the nasal seal 202 and its under-nose support224 in a rest state, i.e. un-used. Like the contacting surface 220 ofthe nasal seal, the under-nose support 224 is also configured to be softand flexible or pliable such that its shape and position may conform ina sling or hammock like manner to the under-nose surface of the user'snose when the nasal mask interface is secured to the user's face or isotherwise worn. In this embodiment, the under-nose support isnon-stretchable in any direction, although it may have a degree ofstretching in same directions in alternative embodiments.

Alternative Under-Nose Support

The main lateral portion 229 or band of the under-nose support 224 isgenerally U-shaped with some curvature across the lateral width of theunder-nose support. In alternative embodiments, the under-nose supportmay have flat sections or portions, or generally more rectangular orsquarish in shape. For example, referring to FIG. 61 , in alternativeembodiments, the under-nose support indicated at 224A may have asubstantially flat central horizontal portion 229A, and twosubstantially vertical or upright portions 229B extending upwardly froma respective end of the central horizontal portion 229A and eachconnecting at connecting points 229C to an inner surface on each upperlater side of the nasal seal either directly or via a rib as with theprevious embodiment.

Example of Nasal Seal Dimensions

In this embodiment, the ratio of the overall height to overall lateralwidth of the nasal seal 202 is in the range of approximately 1:1 toapproximately 1:1.4, and in this example embodiment approximately 1:1.2,in this embodiment, the ratio of the overall height to overall lateralwidth to overall depth of the nasal seal is in the range ofapproximately 1:1:0.6 to approximately 1:1.4:1, and in this exampleembodiment approximately 1:1.2:0.8.

By way of example, the main dimensions of aspects of one nasal sealconfiguration will be described to provide a sense of scale. Referringto FIG. 47 , the height of the nasal aperture defined by contactingsurface edge 222 indicated in the central region at 242B is in the rangeof approximately 8 mm to approximately 43 mm, preferably approximately23 mm and the outermost width of the nasal aperture indicated at 242A isin the range of approximately 24 mm to approximately 49 mm, preferablyapproximately 34 mm. The overall height of the nasal seal as indicatedat 242D is in the range of approximately 22 mm to approximately 72 mm,preferably approximately 47 mm, and the overall width as indicated at242C is in the range of approximately 47 mm to approximately 87 mm,preferably approximately 57 mm. In this embodiment, the width of thecentral connecting portion 232 in the reduced width middle region is inthe range of approximately 2 mm to approximately 15 mm, preferablyapproximately 3 mm as indicated at 242E. Referring to FIG. 52 , theoverall depth of the nasal seal indicated at 243A is in the range ofapproximately 29 mm to approximately 49 mm, preferably approximately 39mm. The depth of the nasal seal between the lateral contacting surfaceand lateral edge of the housing aperture as indicated at 243B is in therange of approximately 21 mm to approximately 36 mm, preferablyapproximately 31 mm. The depth of the nasal seal between the centralnasal bridge valley 245 of the contacting surface 220 and thecorresponding central housing aperture edge 227 is in the range ofapproximately 18 mm to approximately 33 mm, preferably approximately 28mm. The lateral width of the nasal seal between the outer lateral pointsof the connecting edge 227 at the outer side of the nasal seal is in therange of approximately 40 mm to approximately 50 mm, preferablyapproximately 49 mm. Referring to FIG. 54 , the height of the nasal sealbetween the bottom edge 222 of the nasal aperture 206 and the bottomsurface of the nasal seal 202 is in the range of approximately 5 mm toapproximately 20 mm.

Referring to FIG. 58 , the thickness of the main lateral portion 229 ofthe under-nose support 224 in a direction transverse to the contactingsurface of the main lateral portion as indicated at 244A is in the rangeof approximately 0.2 mm to approximately 3 mm, preferably approximately1.1 mm. The central connecting portion 232 extending from the centre ofthe main lateral portion 229 starts with a similar thickness and thentransitions to a thinner thickness as shown as it connects to the nasalaperture edge 222 of the contacting surface 220. In this exampleembodiment, the thickness in the edge region 236 of the contactingsurface is approximately 0.2 mm.

The dimensions of various aspects of the nasal seal may be varied toprovide for different sized patients. In one embodiment, the nasal sealand interface may be provided in a number of different sizes such assmall, medium and large, or a larger number of size categories. Inanother embodiment, the nasal seal may be provided in two sizes, such asa small-medium size and a medium-large size. By way of example,dimensional aspects of a small-medium nasal seal compared to amedium-large nasal seal will be provided by way of example, withreference to FIGS. 59-67 . Referring to FIGS. 59 and 60 , the radius ofcurvature R of a central region 235 of the main lateral band 229 of theunder-nose support is in the range of approximately 8 mm toapproximately 18 mm, preferably for a small-medium nasal seal isapproximately 12.5 mm, and for a medium-large size nasal seal thecentral region 235 is longer and comprises a substantially constantlarger radius of curvature of approximately 14 mm. Referring to FIGS. 62and 63 , the width of the central connecting portion 232 in the middlethin region is approximately 2.9 mm for a small-medium sizeconfiguration and approximately 4.12 mm for a medium-large sizeconfiguration. Referring to FIGS. 64 and 65 , the angular offsetindicated at 239 between the axis AH of the central region of the mainlateral portion 229 and the seal tangential axis AG is approximately 64°for a small-medium size configuration and approximately 58° for amedium-large configuration. Referring to FIGS. 66 and 67 , the nasalbridge region of the contacting surface of the nasal seal comprises arecessed valley portion 245 as previously described. In this embodiment;the depth of the valley region 245 as indicated at 245B is approximately7 mm for both the small-medium and medium-large size configurations. Thewidth of the valley region as indicated at 245A is in the range ofapproximately 7 mm to approximately 17 mm, preferably approximately13.81 nm for the small-medium size configuration, and approximately 14.1mm for the medium-large configuration.

As described, the nasal seal is generally dimensionally and/orconfigured so as to have a generally rectangular shape when viewed fromthe outer side as shown in FIG. 48 and from the front or face-contactingside as shown in FIG. 47 .

Seal Housing

Referring to FIGS. 68-74 , the seal housing 204 of this embodiment ofthe nasal mask interface 200 will be described in further detail. Inthis embodiment, the seal housing 204 is formed of a rigid material oris more rigid that the flexible nasal seal. For example, the sealhousing may be formed from a plastic polymer such as polycarbonate orsimilar.

The seal housing or shell 204 is a generally hollow component thatextends from a main opening on the seal connecting side indicated at 262to an outer side indicated at 261 (see FIG. 72 ). The opening on theseal contacting side 262 of the seal housing 204 is defined by aperimeter edge 263 of the seal housing 204, The seal housing 204 isgenerally defined by a concave shaped exterior surface that extends fromthe perimeter edge 263 of the opening to the outer side 261 of the sealhousing between top 264A, bottom 264B and lateral sides 264C, 264D ofthe seal housing to thereby provide a substantially hollow componentwith depth that cooperates with the nasal seal 202 to collectivelydefine a mask cavity or volume for receiving a gases stream from aninlet opening 265 provided on the exterior surface at the outer side 261of the seal housing.

The perimeter edge 263 of the main opening of seal housing 204 isconfigured to connect or couple to the connecting edge 222 of the nasalseal 202 to couple the nasal seal to the seal housing to form the maskcavity. It will be appreciated that the nasal seal 202 and seal housing204 may be permanently or semi-permanently connected or coupled viavarious methods, including overmoulding, welding, adhesive, mechanicalcoupling configuration, or a combination of these.

Referring to FIG. 46 , in this embodiment the connecting edge 222 of thenasal seal 202 is permanently connected or coupled to the perimeter edge263 of the seal housing 204 via adhesive, overmoulding or welding ofcomplementary surfaces at the interface between the edges 222, 263 ofthe components. However, it will be appreciated that in alternativeembodiments that either of the connecting edge 222 or perimeter edge 263may be provided with a channel or a complementary ridge or vice versathat engage with each other to form a mechanical connection, and that inaddition to this mechanical coupling, overmoulding, adhesive, or weldingmay be applied to secure the connection. For example, the ridge andchannel configuration may be similar to that described with reference tothe first embodiment nasal mask interface.

In this embodiment, the shape and dimension of the peripheral edge 263of the seal housing 204 and connecting edge 222 of the nasal seal 202complement each other to enable a secure connection between thecomponents as will be appreciated. In alternative embodiments, it willbe appreciated by a skilled person that the nasal seal 202 may bereleasably connectable to the seal housing 204 via a rigid clip or otherreleasable coupling mechanism if desired.

In this embodiment, the exterior surface of the seal housing 204 isprovided with a channel or recess generally indicated at 266 that formsa yoke channel for releasably receiving and retaining the yoke 208associated with the headgear 250, In this embodiment, the yoke channel266 extends laterally across the exterior surface of the seal housing204 in a middle or upper region of the seal housing. Below the yokechannel 266 at or toward the bottom of the seal housing is a centralinlet opening 265 that is configured to receive a supply of gases intothe nasal mask interface when in use. In this embodiment, the inletopening 265 of the seal housing 204 is configured to releasably coupleto a conduit frame 211 that is in turn releasably or permanentlyconnected to an end of a gases supply conduit 260 as previouslydescribed.

In this embodiment, the inlet opening 265 of the seal housing 204 issubstantially oval in shape with the major axis extending laterallyacross the seal housing. As such, when viewed from the outside as shownin FIG. 70 , the inlet opening 265 is wider in the lateral directionthan it is high. As shown in FIG. 72 , the inlet opening 265 issubstantially symmetrical relative to a plane 265A extending through themajor axis of the oval aperture, such as indicated by line AE in FIG. 42. With reference to FIGS. 70 and 74 , the inlet opening 265 forms aconduit portion through the front wall surface of the seal housing 204in that is has depth around at least portions of the perimeter. Forexample, the inlet aperture 265 comprises upper 265C and lower 265Bsurfaces extending into the seal housing from the outer surface to theinner surface of the seal housing. In this embodiment, protrusions offormations 267 are provided across the upper and lower surfaces 265B,265C of the inlet aperture 265. In this embodiment, the protrusions 267are elongate protrusions extending along a central portion of theperimeter of the oval aperture 265 in the upper and lower regions at ortoward the inner surface of the seal housing. In operation, theprotrusions 267 engage with complementary recesses or channels 287 ofthe conduit frame 211 to provide a snap-fit releasable engagement of theconduit frame into the inlet aperture 265.

In this embodiment, as shown in FIG. 72 , at least a portion of theupper and lower regions of the inlet aperture 265 protrude beyond themajority of the front surface of the seal housing 204. Referring toFIGS. 70 and 74 , in this embodiment the inlet aperture configuration isalso provided with recessed regional regions about at least a portion ofthe periphery of the inlet aperture as indicated at 268. In thisembodiment, the inlet aperture 265 is provided with two discreterecessed regions or surfaces indicated at 268 at or toward each of thelateral sides of the inlet aperture. In this embodiment, the recessedregions 268 terminate prior to meeting each other, although inalternative embodiments it will be appreciated that a recessed regionmay extend around the entire perimeter of the oval inlet aperture 265.In operation, the recessed regions 268 are shaped and dimensioned toreceive complementary engagement surfaces of the conduit frame 211 suchthat the interface region between the conduit frame and outer peripheralsurface of the seal housing surrounding the inlet aperture issubstantially smooth or flush to provide a continuous or blended outersurface when the conduit frame 211 is assembled into the inlet aperture265 of the seal housing 204.

In this embodiment, the yoke channel 266 is provided with locatingfeatures 271 that engage with complementary locking features provided onthe yoke 208. In this embodiment, the locating features 271 of the yokechannel 266 are recessed formations into which complementary locatingprotrusions or formations provided on the yoke 208 engage to lock theyoke 208 to the seal housing 204. In this embodiment, the recesses 271of the yoke channel 266 and complementary protrusions on the yoke 208are aligned such that when the components are engaged together with theyoke protrusions engaged within their complementary recesses 271 of theyoke channel, the yoke is slightly deformed such that a residual tensileor compressive force exists that locks or secures the two componentstogether. The yoke channel 266, yoke 208, and headgear assemblygenerally will be described in further detail later.

The seal housing 204 comprises a bias flow vent 212 in the form of anarrangement of inlet apertures. In this embodiment, the seal housing 204comprises an arrangement of one or more arrays of bias vent holes. Inthis embodiment, the seal housing 204 comprises three separate linearrays of spaced bias vent holes. Firstly, an upper array 212 of biasvent holes extends across the upper surface of the seal housing abovethe yoke channel 266 as indicated at 212A. In this embodiment, the upperhorizontal row or array of bias vent holes extends substantially acrossthe entire width of the upper region of the seal housing between thelateral sides. A vertical line array of bias vent holes 212B, 212C isalso provided on each of the lateral sides of the seal housing on eitherside of the inlet aperture 265. As shown, the vertical arrays of biasvent holes 212B, 212C extend from below the yoke channel 266 andterminate at or toward the lower surface of the seal housing 204. Inthis embodiment, the holes or apertures of the arrays 212A, 212B, 212Care laser drilled, but could be formed by alternative means.Additionally, it will be appreciated that each of the upper 212A andlower lateral 212B and 212C vent arrays may comprise multiple linearrays or rows in that the configurations are not limited to singularline arrays. Additionally, the arrays of apertures need not be uniformlyspaced in alternative configurations. The configuration shown with upper212A and lower lateral 212B, 212C vent arrays is configured to preventnoise and draft when the nasal mask interface is used. Alternatively, oradditionally, the bias vent holes may be provided on the conduit frame211.

Referring to FIGS. 70, 71 and 72 , example dimensions of a configurationof the seal housing 204 will be provided by way of example only toprovide a sense of scale. Referring to FIG. 71 , the overall height ofthe seal housing 204 between the top 264A and bottom 264B surfaces asindicated at 272A is in the range of approximately 19 mm toapproximately 59 mm, preferably approximately 39 mm, and the overallwidth of the seal housing between the lateral sides 264C and 264D asindicated at 272B is in the range of approximately 45 mm toapproximately 75 mm, preferably approximately 50 mm. Referring to FIG.72 , the overall depth of the seal housing between the seal contactingside 262 and outer side 261 as indicated at 272C is in the range ofapproximately 19 mm to approximately 49 mm, preferably approximately 24mm. Referring to FIGS. 68 and 70 , in this example the distance orheight between the top surface 264A and upper inner surface 266A of theyoke channel 266 in the centre of the seal housing as indicated at 272Dis in the range of approximately 5 mm to approximately 20 mm, preferablyapproximately 10 mm. In this embodiment, the diameter 272F of theapertures in the bias flow vent arrays 212A, 212B, 212C is in the rangeof approximately 0.6 mm to approximately 0.8 mm, preferablyapproximately 0.7 mm.

Conduit Frame

Referring to FIGS. 75-81 , the conduit frame 211 that releasably engagesinto the inlet aperture 265 of the seal housing 204 will be described infurther detail.

In this embodiment, the conduit frame 211 is configured to releasablyengage or connect into the inlet aperture 265 of the seal housing via asnap-fit engagement, although it will be appreciated that any otheroperable mechanism or mechanical coupling arrangement for releasablyconnecting these components may alternatively be used.

In this embodiment, the conduit frame 211 comprises a main hollow bodythat extends from a first end 283A that is configured to engage into theair inlet aperture 265 of the seal housing 204 to a second end 283B thatis configured to connect or couple with an end of a gases supply conduiteither directly or indirectly via a connector. The conduit frame 211, asshown in FIGS. 81 and 82 , forms a hollow conduit along the longitudinalaxis of its main body between its first 283A and second 283B ends. Theconduit is open at each end of the main body and in this embodiment issubstantially oval in cross-sectional shape along the length of the mainbody of the conduit frame 211. Referring to FIG. 79 , in this embodimentthe internal circumference of the oval conduit extending through themain body varies along the length of the main body from the first end283A to the second end 283B In this embodiment, the circumference of theconduit at the first end 283A (connecting to the seal housing) is largerrelative to the circumference of the oval conduit at the second end 283B(connecting to the gasses supply conduit) to create a funnel-likeprofile.

Referring to FIGS. 79 and 80 , in this embodiment the conduit frame 211is symmetrical about at least a horizontal plane extending through thelongitudinal axis AI (see FIG. 79 ) as indicated at AJ (see FIG. 80 ).In this embodiment, the axis of symmetry AJ corresponds to the majoraxis extending through the oval conduit. This symmetry corresponds tothe symmetry of the inlet aperture 265 of the seal housing 204 andenables the conduit frame 211 to be connected to the seal housing 204 ineither of two orientations. In other words, the conduit frame 211 may beremovably coupled into the inlet aperture 265 of the seal housing ineither of two orientations that are rotated 180° relative to each other.In this embodiment, the conduit frame 211 is also symmetrical relativeto a vertical plane indicated at AK that extends along the longitudinalaxis AI of the conduit frame. The vertical plane corresponds to theminor axis of the oval-shaped conduit, and is orthogonal or transverseto the horizontal plane AJ. In particular, the conduit frame issymmetrical relative to two transverse planes extending through thelongitudinal axis of the conduit frame.

Referring to FIG. 75 , in this embodiment the main body of the conduitframe 211 comprises a central gripping portion 284, a first connectingportion 285 at the first end 283A for connecting to the inlet aperture265 of the seal housing, and a second connecting portion 286 at thesecond end 283B for connecting to a gases supply conduit.

The seal housing connecting portion 285 extends from a first end 284A ofthe central gripping portion 284 and terminates at the first end 283A ofthe conduit frame. The conduit connecting portion 286 extends from asecond end 284B of the central gripping portion 284 and terminates atthe second end 283B of the conduit frame 211. As shown in the Figures,both the seal housing connecting portion 285 and conduit connectingportion 286 are oval in cross-section relative to the longitudinal axisof the conduit frame. In this embodiment, with reference to FIG. 79 ,both the exterior circumference of the connecting portions 285, 286reduce or taper from their respective ends of the central grippingportion 284 to their respective ends 283A, 283B of the conduit frame211. It will be appreciated that the conduit frame may have alternativeshape profiles to oval in alternative embodiments. For example, theconduit frame may have an internal conduit having a circularcross-section in alternative forms.

In this embodiment, the gripping portion 284 comprises upper and lowerrecessed grip portions 284C, 284D on the upper and lower surfaces of theconduit frame. The recessed grip regions 284C, 284D on the upper andlower surfaces enable a user to use a pinch grip between a thumb andforefinger to insert or release the conduit frame 211 from the sealhousing in use when desired.

In this embodiment, the central gripping portion 284 increases in widthat the lateral sides toward the first end 284A to form winged regions284E, 284F of a lip protruding from the lateral sides of the conduitframe. In this embodiment, the first end 284A of the central grippingportion is substantially concave in shape as shown in FIG. 77 . In thisembodiment, the inner surfaces 284G, 284H of the winged regions 284E,284F adjacent the seal housing connecting portion 285 are complementaryin shape and size to the recessed lateral regions 268 of the inletaperture 265 of the seal housing. In particular, the inner surfaces284H, 284G of the winged regions of the conduit frame 211 abut or engagewith the complementary recessed regions 268 associated with the inletaperture 265. In this embodiment, the exterior or outer surface profileof the gripping portion 284 in the regions indicated at 2841 and 284Jassociated with the winged regions have a curvature or a shape thatcomplements the curvature or shape of the seal housing on the lateralsides of the inlet aperture 265. This complementary shape of the wingedregions 284L 284J provides a flush and continuous surface profile at theexternal mating or interface region of the conduit frame 211 and sealhousing 204 when they are assembled together. The concave profile of thefirst end 284A of the gripping portion or region 284 is configured orarranged to complement the concave surface profile adjacent orsurrounding the periphery of the inlet aperture 265 of the seal housing204 to provide a continuous and flush or blended external surface at theinterface between the conduit frame and seal housing when assembledtogether.

Referring to FIGS. 75 and 77 , the upper and lower portions of the sealhousing connecting portion 285 at the first end 283A of the conduitframe are provided with undercut or recessed grooves 287. These grooves287 are shaped and dimensioned to complement the upper and lowerprotrusions 267 of the inlet aperture 265 of the seal housing to enablethe conduit frame 211 to engage securely into the inlet aperture 265 ofthe seal housing via a snap-fit engagement.

In this embodiment, as shown, the main body of the conduit frame 211 isa substantially ovular body along its length between the first 283A andsecond 283B ends. However, it will be appreciated that alternativecross-sectional shapes may be used for the internal conduit and/orgeneral shape of the body in alternative embodiments if desired such ascircular or other suitable shape. In this embodiment, the ovular mainbody is slightly deformable with respect to at least the vertical planeaxis AK extending through the longitudinal axis of the body. Thisenables the grip regions 284C, 284D to be compressed toward each otherby a user to slightly deform the conduit frame 211 and thereby enabledisengagement of the snap-fit connection between the conduit frame 211in the seal housing 204 to enable the conduit frame (and its associatedgasses supply conduit) to be removed or disconnected from the sealhousing.

Referring to FIGS. 77 and 80 , example dimensions of one configurationof the conduit frame of this embodiment will be described to provide asense of scale. Referring to FIG. 80 , the dimension of the ovalaperture at the conduit connecting end 283B for the major axis 290A isin the range of approximately 9 mm to approximately 29 mm, preferablyapproximately 19 mm, and for the minor axis 290B is in the range ofapproximately 5 mm to approximately 21 mm, preferably approximately 11mm. The oval extrusion of the conduit connecting portion 286progressively increases in dimension to a major axis in the range ofapproximately 14 mm to approximately 34 mm, preferably approximately 24mm, and to a minor axis in the range of approximately 6 mm toapproximately 26 mm, preferably approximately 16 mm, at or toward thegripping portion 284 of the main body. The overall height 290C of theconduit frame 211 between the outermost upper and lower surfaces in thedimension aligned or parallel with the minor axis 290B is in the rangeof approximately 12 mm to approximately 22 mm, preferably approximately17 mm. The overall width 290D of the conduit frame 211 between theoutermost wing regions of the central gripping portion 284 in thedimension aligned or parallel with the major axis 290A is in the rangeof approximately 25 mm to approximately 45 mm, preferably approximately35 mm. Referring to FIG. 77 , the overall length of the conduit framebetween its first and second ends 283A,283B as indicated at 290F is inthe range of approximately 10 mm to approximately 30 mm, and the widthof the seal housing connecting portion 285 as indicated at 290E is inthe range of approximately 14 mm to approximately 34 mm, preferablyapproximately 24 mm. It will be appreciated that the dimensions may bevaried in an alternative embodiments if desired.

Referring to FIG. 79 , the first region indicated 289A of the conduitframe 211 identifies the connection portion 285 that protrudes orextends into engagement into the complimentary inlet aperture 265 of theseal housing 204. The second remaining portion of the conduit frameindicated at 289B toward the second end 283B extends or protrudes fromthe seal housing. It will be appreciated that the first end 283A of theconduit frame 211 may define a housing aperture opening that engages orcompliments the inlet aperture 265 of the seal housing, and the end 283Bthe conduit frame represents a conduit aperture that engages or couplesto an end of a gases supply conduit either directly or via a connector.

Yoke Assembly, Yoke Connection too Seal Housing, and Headgear

With particular reference to FIGS. 82-102 , the yoke 208 and itsconnection to the seal housing 204 and headgear 250 will be explained infurther detail. As previously described, in this embodiment the headgearassembly comprises a yoke or collector 208, which is configured toreleasably attach or couple to the nasal mask assembly, and inparticular the seal housing 204 of the nasal mask assembly.

The yoke 208 is configured to attach to straps of the headgear 250. Inthe embodiment, as shown in FIGS. 35 and 36 , the headgear 200 comprisesan assembly of straps, including a rear strap 258 configured to wrapbehind a patient's head, an upper strap 254 configured to wrap over thetop of a patient's head, and a pair of front or side straps 252configured to extend along the patient's cheeks during use. Each of thevarious straps may be either formed as integral components with somebeing extension portions of the other, and/or otherwise separatelyformed strap portions that are then either permanently connectedtogether or configured for releasable connection to each other. Forexample, in one form shown, the rear strap 258 comprises side extensionsthat form the front or side straps 252 to extend along the patient'scheeks during use, and the upper strap 254 is connected at each end to arespective portion of either the rear 258 or side 252 straps on eachrespective side of the headgear. In another form, each side strap 252 isattached or releasably connected to the rear strap 258 of the headgearassembly, e.g., to a free end of the rear strap 258 or a connectorcoupled to the free end, by a rear connector component, and with theupper strap 254 integrally formed or releasably connected to the rearstrap 258. In yet another form, the upper strap 254 comprises sideextensions that form the front or side straps 252 to extend alongpatient's cheeks during use, and the rear strap 258 is connected(permanently or releasably) at each end to a respective portion ofeither the upper 254 or side 252 straps on each respective side of theheadgear.

In one form, the headgear can be automatically adjustable and/or canincorporate one or more directional locks that allow the headgear toreduce in length with a relatively low amount of resistance and resistan increase in length of the headgear. In some configurations, a lockingforce of the directional locks can be overcome to allow lengthening ofthe headgear for donning of the interface assembly. In some forms theyoke 208 may form a collector for filaments used in an automaticallyadjustable headgear system. In this form, the yoke 208 may incorporateone or more directional locks, each of which can comprise a washermechanism, which may be configured to frictionally engage with thefilament during elongation of the headgear, but allows relativelyfriction-free movement during retraction of the headgear. The washermechanism may be incorporated into the ends of the yoke 208 and the bodyof the yoke may be substantially hollow to receive the filaments withinthe body. The headgear or any portion thereof can be configured inaccordance with any of the embodiments disclosed in Applicant's U.S.Patent Application Publication No. 2016/0082217, U.S. Patent ApplicationPublication No. 2016/0144146, and PCT Patent Application Publication No.WO2016/043603, the entireties of which are incorporated by referenceherein.

Each side strap 256 may comprise a free end to which may be attached aconnector. Each connector may engage with a complementary strapconnector located on the yoke 208. In this embodiment, the yoke 208 issubstantially elongate and comprises a strap connector located at ornear each end of the yoke 202.

The connection between the side straps 256 and yoke 208 may be anysuitable form of connection, such as a snap-fit connection, a screw andthread type connection, or a hooked connection. In one form, each strapconnector of the yoke 208 comprises an end cap 291 (see FIG. 83 )located at each end of the yoke 208. Each end cap 291 may comprise anopening, such as an aperture or recess, configured to receive theconnector of a respective side strap 256 to secure an end cap 291 toeach end of a respective side strap 256. The end caps 291 are theneither releasably (e.g. via a snap-fit arrangement) or permanentlyconnected to a respective end of the yoke 208 to thereby connect yoke208 to the side straps 256 of the headgear assembly. In another form,the free ends of the side straps 256 may be directly coupled orpermanently fixed into a respective end cap 291, which is then eitherreleasably or permanently connected to a respective end of the yoke 208to thereby connect the yoke to the side straps 256 of the headgearassembly.

Referring to FIGS. 68, 70 , and FIGS. 82-87 , as mentioned above, theyoke 208 is also configured to attach to the seal housing 204 of thenasal mask interface. In one form, as discussed, the seal housing 204may comprise a recessed region or yoke channel 266 configured to receiveat least a portion of the yoke 208 therein when the yoke 208 and sealhousing 204 are attached together. The yoke channel 266 is formed ordefined by an upper wall 266A, rear wall 266C, and lower wall 266B. Inthis embodiment, the yoke 266 has asymmetry between upper 292A and lower292B edges of the yoke 208. In the illustrated embodiment, the upperedge 292A of the yoke 208 is straighter than the lower edge 292B (seeFIG. 86 ). The asymmetry advantageously provides improved visual cues asto the correct orientation for assembly of the yoke 208 into the yokechannel 266 of the seal housing 204 and helps inhibit incorrectassembly.

As shown in FIGS. 68 and 70 , the yoke channel 266 of the seal housing204 includes locating features or connector recesses 271 in the upper266A and lower 266B walls. In the illustrated embodiment, a connectorrecess 271 is positioned at, adjacent, or proximate each lateral end ofthe yoke channel 266. The connector recesses 271 at least partiallydefine or form retention lips 271A at or along front edges of the yokechannel 266 (e.g., at or along front edges of internally facing surfacesof the upper wall 266A and lower wall 266B). The yoke 208 includesconnector protrusions 293 protruding rearwardly from upper, lower,and/or rear surfaces of the yoke 208. In the illustrated embodiment, theyoke 208 includes a connector protrusion 293 on each side of a center ofthe yoke 208. In the illustrated embodiment, the yoke 208 includes ayoke front 294A and yoke back 294B that are coupled together, asdescribed in greater detail herein, and the connector protrusions 293are formed in the yoke back 294B. The connector recesses 271 of the yokechannel 266 are configured to receive the complementary connectorprotrusions 293 when the seal housing 204 and yoke 208 are coupledtogether to form a snap-fit connection between the seal housing 204 andyoke 208. When the seal housing 204 and yoke 208 are coupled together,the retention lips 271A engage the yoke 208 forward of the connectorprotrusions 293 to contribute to the snap-fit connection and retain theyoke 208 in the yoke channel 516. In the illustrated embodiment, theconnector protrusions 293 and connector recesses 271 have a square orrectangular profile, which inhibits the yoke 208 from rotating out ofthe yoke channel 266.

In some embodiments, the yoke 266 has an oval or substantially ovalcross-section along its length, for example. This shape advantageouslyreduces the size or bulk of the yoke 266 and/or provides an improvedaesthetic appearance. The washer housings 295 of the directional locks,discussed in greater detail herein, can have a D-shaped, substantiallyD-shaped, U-shaped, or substantially U-shaped cross-section, for exampleas shown in FIGS. 88-89 , to allow for and/or contribute to the overalloval or substantially oval cross-section of the yoke 266. A washerhousing 295 is located at or toward each end of the yoke 266 within thebody. Only the right washer housing 295 is shown in one end of the yokein FIGS. 88-89 for clarity, with the mounting space 295A of the otheromitted left washer housing shown at the other end. The pair of washerhousings 295 can be oriented opposite each other (see FIG. 91 ). Inother words one of the washer housings 295, e.g., the right washerhousing 295 as shown in FIG. 136C, can be oriented as an upward-facingU-shape, and the other washer housing, e.g., the left washer housing(omitted from view), can be oriented as a downward-facing U-shape. Thisarrangement and orientation can advantageously help allow the line orfilament tracks 296A, 296B to extend above and below the left and rightwasher housings 295, respectively, as discussed in greater detailherein.

In some embodiments, the yoke 208, or a central portion of the yoke 208,has a depth (when viewer from the top, e.g. FIG. 84 ) that is the sameas or similar to or corresponds to a depth of the yoke channel 266 suchthat the yoke 208 does not protrude, or does not substantially protrude,from the yoke channel 266. In other embodiments, as shown in FIG. 46 ,at least a portion of the yoke 208 may protrude beyond the yoke channel266.

As shown in FIGS. 84 and 85 , in the illustrated embodiment, a rear orback surface of the yoke 208 includes a rearward step or transition oneach side or lateral end 302 of the central portion 300 of the yoke 208such that the yoke 208 has a stepped or varying depth (when viewed fromthe top). In other words, lateral portions 302 of the yoke 208, whichare positioned laterally outside of the yoke channel 266 when the yoke208 is coupled to the seal housing 204, have a greater depth 304 (in atleast the front to back surface direction) or thickness than the depthor thickness 306 of the central portion 300 of the yoke 208, which ispositioned in the yoke channel 266 when the yoke 208 is coupled to theseal housing 204. The steps or transitions form or define abutmentsurfaces 308 at the transitions between the central portion 300 andlateral portions 302 of the yoke 208. When the yoke 208 is coupled tothe seal housing 204, each of the abutment surfaces 308 abuts or ispositioned adjacent or proximate one of the lateral edges or surfaces310 (see FIGS. 68 and 72 ) of the seal housing 204. The abutmentsurfaces 308 and lateral edges 310 help properly align the yoke 208 withthe seal housing 204 during assembly. The abutment surfaces 308 andlateral edges 310 also or alternatively provide a more secure connectionbetween the yoke 208 and seal housing 204. The reduced depth orthickness of the central portion of the yoke 208 advantageously reducesthe overall size of the seal housing 204 and yoke 208 assembly.

As previously described, in this embodiment the yoke 208 has asymmetrybetween its upper edge or surface 292A and lower edge or surface 292B.Referring to FIG. 86 , in this embodiment, the upper edge 292A isstraighter than the lower edge 292B. In this embodiment, the heightprofile of the yoke 208 (when viewed from the front, e.g. FIG. 86 )varies across the lateral width of the yoke between the end caps 291. Inthe illustrated embodiment, as shown in FIGS. 86 and 87 , the height ofthe yoke 208 in a central region 300 that is generally received in theyoke channel 266 of the seal housing is reduced relative to the heightof the yoke in the lateral side regions 302. In this embodiment, theheight of the yoke in the central region 300 gradually reduces via acurved (e.g, concave) surface profile of the lower edge 292B of the yokein the central region to an apex at the center of the yoke at which itis of most reduced height.

Referring to FIGS. 84-87 , in this embodiment the varying depth (viewedfrom top) and height (viewed from front) profiles of the yoke 208 alongis length provide a varying overall thickness profile along the yokeslength. For example, the overall thickness (in depth and height) of theyoke in the central region 300 is smaller or thinner than the overallthickness (in depth and height) of the lateral regions 302. Inparticular, the yoke can be considered as having a thin central region300, and thicker lateral regions 302 either side of the central region.The thinner region 300 is generally received in the yoke channel 266 ofthe seal housing 204, while the thicker lateral regions do not contactthe seal housing 204 and extend outwardly away from the sides of theseal housing. The length, thickness, and convex curvature profile of theyoke are configured to blend in with the seal housing, and alsoconfigured such that the lateral sides of the yoke do not contact theuser's face in use.

Referring to FIGS. 84 and 85 , in this embodiment, the radius ofcurvature of the yoke 208 (when viewed from the top) is substantiallyconstant in majority of the thinner central region 300 of the yoke, andthen the radius of curvature increases or is larger at the thickerlateral sides 302 of the yoke. In some embodiments, the thicker lateralregions 302 may extend at a substantially constant angle along theirlength, without any curvature.

Referring to FIG. 86 , the overall width 301A of the yoke 208 betweeneach lateral edge (e.g. when viewed from the front like in FIG. 86 )will be in the range of approximately 60 mm to approximately 120 mm.Referring to FIG. 87 , the overall depth 301B of the yoke 208 front tothe rear end caps 291 (e.g. when viewed from the side like in FIG. 87 )will be in the range of approximately 30 mm to approximately 55 mm.

As shown in FIG. 83 , in the illustrated embodiment, the yoke 208includes a yoke front 294A and a yoke back 294B. The yoke 208 can alsoinclude two end caps 291, one at each lateral end of the yoke 208. Inthe illustrated embodiment, the yoke front 294A and yoke back 294B areformed as separate components that are coupled together. In thisembodiment, a split line 312 (shown in FIG. 82, 84, 35 ) between theyoke front 294A and yoke back 294B is centered or generally centered.This can improve ease of manufacturing.

The yoke front 294A and yoke back 294B can be coupled together via asnap fit. In the illustrated embodiment, the yoke front 294A includes ayoke fastener 314 projecting rearwardly from a rear surface of the yokefront 294A. In the illustrated embodiment, the yoke fastener 314 ispositioned centrally or generally centrally with respect to the yokefront 294A. The yoke back 294B includes a fastener aperture or recess316 that is sized, shaped, and positioned to receive the yoke fastener314 to form a snap-fit connection when the yoke front 294A and yoke back294B are coupled together. The central connection between the yoke front294A and yoke back 294B via the yoke fastener 314 and fastener apertureor recess 316 provides more rigidity to the connection between the yokefront 294A and yoke back 294B and/or provides support against orinhibits twisting between the yoke front 294A and yoke back 294B. Insome embodiments, the yoke front 294A instead includes the fasteneraperture or recess 316 and the yoke back 294B includes the yoke fastener314. In some embodiments, the fastener aperture or recess 316 includesone or more fastener or interference bumps 318 (see FIG. 88 ) extendingalong (e.g., laterally along) upper and/or lower edges of the fasteneraperture or recess 316 and protruding into the fastener aperture orrecess 316 from the upper and/or lower edges. In some embodiments, theyoke fastener 314 includes one or more corresponding notches extendingalong (e.g., laterally along) upper and/or lower surfaces of the yokefastener 314 that are sized, shaped, and positioned to receive thefastener bump(s) 318 to form a snap-fit connection. In some embodiments,the fastener aperture or recess 316 includes one or more notches 320 andthe yoke fastener 314 includes one or more fastener bumps 318. In someembodiments, the interference bumps 318 may simply assist in form aninterference fit by engaging with the surface of the yoke fastener 314.

The illustrated embodiment shows a fastener recess 316 that does notextend all e way through the thickness of the yoke back 294B. In avariation, a fastener aperture 316 may be provided alternatively, whichdoes extend through the entire thickness of the yoke back 294B. However,the fastener recess 316 configuration can advantageously allow foreasier manufacturing, provide a neater finish (without an aperture inthe yoke back 294B), and/or inhibit the ingress of dirt or other debrisinto the line tracks 296A, 296B (due to the lack of aperture, whichallows the yoke 208 to be fully enclosed along its length), which canhelp maintain the function of the automatic headgear adjustmentmechanism. Either form of fastener aperture or fastener recess functionsto receive the complementary yoke fastener 314 in a snap-fit and/orfriction fit engagement as described above when the yoke front 294A andyoke back 294B are coupled together.

In this embodiment, the yoke back 294B includes an upper alignment bead322 a protruding forward from the yoke back 294B and extending along alength of the yoke back 294B adjacent or proximate the upper surface ofthe yoke back 294B, and/or a lower alignment bead 322 b protrudingforward from the yoke back 294B and extending a length of the yoke back294B adjacent or proximate the lower surface of the yoke back 294B. Theyoke front 294A (see FIG. 90 ) includes an upper alignment groove 324 ain a rear surface of the yoke front 294A extending along a length of theyoke front 294A adjacent or proximate the upper surface of the yokefront 294A, and/or a lower alignment groove 324 h in the rear surface ofthe yoke front 294A extending a length of the yoke front 294A adjacentor proximate the lower surface of the yoke front 294A. The upper and/orlower alignment grooves 324 a, 324 b receive the upper and/or loweralignment beads 322 a, 322 b, respectively, when the yoke front 294A andyoke back 294B are coupled together. The alignment beads 322 a, 322 band alignment grooves 324 a, 324 b help correctly align the yoke front294A and yoke back 294B. The alignment beads 322 a, 322 b and alignmentgrooves 324 a, 324 b can also or alternatively resist or support againsttorsion, e.g., between the yoke front 294A and yoke back 294B. In someembodiments, the alignment beads 322 a, 322 h and alignment grooves 324a, 324 b can be positively engaged with each other, for example, in theform of a friction fit or snap fit connection.

The end caps 291 can help secure the yoke front 294A and yoke back 294Btogether by clipping over or snap fitting over or onto the lateral endsof the yoke front 294A and yoke back 294B. The end caps 291 can alsoallow for connection of a front strap of a headgear to the yoke 208. Insome embodiments, each end cap 291 is over-molded onto a braided portionof the front strap.

As shown in FIGS. 93-98 , the lateral ends of the yoke front 294A andyoke back 294B include or are formed by end cap inserts 326. The end capinserts 326 can be integrally formed with or attached to the lateralends of the yoke front 294A and yoke back 294B. The end cap inserts 326have a reduced dimension or profile compared to the lateral portions ofthe yoke 208. The end caps 291 have internal cavities 328 that receivethe end cap inserts 326. During assembly, the end caps 291 are connectedover or snapped onto the end cap inserts 326 in a hinged manner, asshown in FIG. 93 .

As shown in FIG. 98 , each end cap 291 includes a retention hole 330 onone side (e.g., in a rear side in the illustrated embodiment) and aretention notch 332 on an opposite side (e.g., a front side in theillustrated embodiment), In other embodiments, the position of theretention hole 330 and retention notch 332 can be reversed. Thepositioning of the retention hole 330 in the rear of the end cap 291 inthe illustrated embodiment, advantageously hides the retention hole 330in use, which provides an improved aesthetic appearance. The retentionnotch 332 extends from the end cap cavity 328 forward into the end cap291. The end cap inserts 326 include a first retention feature 334 onone of the front and back surfaces (e.g., extending rearwardly from theyoke back 294B portion of the end cap insert 326 in the illustratedembodiment) and a second retention feature 336 on an opposite surface(e.g., extending forward from the yoke front 294A portion of the end capinsert 326 in the illustrated embodiment). To attach the end cap 291 tothe yoke 208, e.g., to the end cap insert 326, the retention hole 330 isengaged with the first retention feature 334 as shown in FIG. 94 . Thefirst retention feature 334 then acts as a hinge or pivot point, and theend cap 291 is pivoted over the end cap insert 326 in the directionindicated by the arrow in FIG. 93 until the second retention feature 336and retention notch 332 engage, e.g., in a hump or snap fit connection.The hinged connection can provide a strong connection between the yoke208 and end caps 291 with a reduced end cap insert 326 length 338(indicated in FIG. 144 ). The end caps 291 can therefore taper moresteeply. The reduced length of the end cap inserts 326, end caps 291,and/or overall yoke 208 can advantageously reduce or minimize the yoke208 digging into the patient's face.

In the illustrated embodiment, the first retention feature 334 is orincludes an oval or stadium shaped post extending rearward from the yokeback 294B. The first retention feature 334 has a length or depthselected such that an outer or rearmost surface of the first retentionfeature 334 is flush or substantially flush with the rear surface of theyoke back 294B. This increases the contact area and interaction betweenthe end caps 291 and end cap inserts 326 and increases the retentionforces. The connection between the end caps 291 and end cap inserts 326can therefore resist greater torsional forces along the length of theyoke 208 and/or rotational forces about the joint.

In the illustrated embodiment, the second retention feature 336 is orincludes a raised tab extending forward from the yoke front 294A. Thesecond retention feature 336 has a reduced length or depth compared tothe first retention feature 334, which allows the end cap 291 to passover the second retention feature 336 during assembly. In theillustrated embodiment, the second retention feature 336 has a chamferedlead-in 336 a on one edge, e.g., on the lateral (relative to the yoke208) edge in the illustrated embodiment, which allows the end cap 291 tobe hinged or pivoted over and/or onto the second retention feature 336more easily.

In some embodiments, the end caps 291 can be over-molded onto an end ofa braided element (e.g. side strap 252) of an automatic headgearadjustment mechanism, for example, braided elements as shown anddescribed in U.S. Provisional Patent Application No. 62/343,711,entitled “Directional Lock for Interface Headgear Arrangement” and filedMay 31, 2016, PCT Application No. PCT/IB2017/051522, and PCT ApplicationPublication No. WO2014/175752, the entireties of which are herebyincorporated by reference herein. The core elements or filaments 340 canextend within the braided elements (e.g. side straps 252). The end caps291 can connect the braided element, and therefore the headgear, to theyoke 208 and create a closed loop headgear system.

As described herein, in some embodiments, the yoke 208 may form acollector for core elements, such as filaments 340, used in anautomatically adjustable or self-adjusting headgear system. As shown inFIG. 91 , the yoke front 294A includes an upper line track 296A and alower line track 296B, In this embodiment, a line track dividerprotrudes rearwardly from a rear or internal surface of the yoke front294A. In some embodiments, the yoke fastener 314 forms or functions asthe line track divider extends generally at a diagonal across a portionof the length of the yoke front 294A. In the illustrated embodiment, adivider wall 344 extends between each of the washer housings 295 and theopposing line track. The divider wall 644 separates the opposing linetrack from the washer housing 295 so that a free end of the filament 340is inhibited from being caught in the opposing washer housing 295 duringretraction. In the illustrated embodiment, the line tracks 296A, 296Bare not symmetrically mirrored due to the asymmetry of the upper andlower edges of the yoke 208.

FIG. 92 illustrates a variation of the yoke 208 in which the line tracks296A, 296B extend into and terminate within the end caps 291. Thelengths of the line tracks 296A, 296B are therefore extended beyond theends of the yoke front 294A and yoke back 294B. This increases thelength of filament 340 that can be stored within the yoke 208, whichincreases the range of adjustment or variability in the size of theheadgear. The headgear assembly defines a headgear loop that extendsaround a user's head in use. The filament 340 forms part of theautomatic headgear adjustment mechanism that allows a total length ofthe headgear loop to be extended during donning and doffing of the masksystem. In some such embodiments, the length of each of the line tracks296A, 296B can be increased or extended by about 5 mm. In suchembodiments, the total length of the headgear loop, in an extendedstate, can therefore increase by about 10 mm.

Referring to FIGS. 99-102 , show an embodiment of a directional lock ofthe automatically adjusting headgear that will be explained in furtherdetail. The directional lock comprises a washer housing 295, a first anda second lock element (e.g., washer 1820, 1822) and a filament or coremember 340. The housing comprises a first and a second chamber 1840,1842 wherein the first and second chambers 1840, 1842 are configured tohouse the first and second lock washers 1820, 1822, respectively. In theillustrated arrangement, the first and second chambers 1840, 1842 areseparated by an internal wall 1812 of the housing 295. However, in otherarrangements, the first and second chambers 1840, 1842 are notnecessarily physically separate spaces, but can be portions of achamber. The housing 295 has two end walls 1814, which along with theinternal wall 1812, have an elongate core opening 1860 for the coremember 340 pass through. The core openings 1860 are substantiallyaligned with each other. The core opening 1860 of the end wall 1814shown on the right side of the figures is larger than the core openingof the internal wall 1812 and the end wall 1814 shown on the left of thefigures. This allows for manipulation of the path of the core member 340through the housing 295. The first and second chambers 1840, 1842 areeach delimited by the internal wall 1812, one of the end walls 1814 anda pair of side walls 1816; wherein the side walls 1816 extend betweenthe end walls 1814 of the housing 295. The first and second chambers1840, 1842 are configured to be open at one or both of a top and abottom of the housing 295.

Each of the first and second chambers 1840, 1842 has a pair of washerretainers 1850 that are aligned on opposing side walls 1816 of thehousing 295. Each pair of washer retainers 1850 is configured topivotally retain one of the first or second lock washers 1820, 1822within the respective first or second chamber 1840, 1842. The washerretainers comprise a circular bush 1852 and an elongate slot 1854,wherein circular bushes 1852 intersect with the bottom of the housingsuch that an entrance is formed. The entrance is configured to allow thefirst and/or second lock washers 1820, 1822 to be received into thewasher retainers 1850. The slot 1854 extends radially from the circularbush 1852 towards the top of the housing 295.

The first and second washers 1820, 1822 comprise a cylindrical shaft1824 and an arm 1826 that extends from the shaft 1824. The cylindricalshaft 1824 is substantially the same width W, as the housing 295 and thearm 1826 is narrower to fit within the first and second chambers 1840,1842, In the illustrated arrangement, the arm 1826 comprises a firstsection 1872 and a second section 1874, wherein the first section 1872extends radially or perpendicularly from the cylindrical shaft 1824 andthe second section 1874 extends at an obtuse angle from the end of thefirst section 1872. The first section 1872 of the arm 1826 of the firstwasher 1820 is shorter than the first section 1872 of the arm 1826 ofthe second washer 1822. The angle between the first and second sections1872, 1874 of the arm 1826 of the first washer 1820 is greater than thecorresponding angle of the second washer 1822. The angles can beselected such that the second section 1874 of one or both of the firstand second washers 1820, 1822 lies substantially flat against thecorresponding wall (e.g., internal wall 1812 and end wall 1814,respectively) of the housing 295 in one position of the washers 1820,1822. The second section 1874 of the arm 1826 comprises a centrallylocated circular aperture 1876 configured to receive the core member340. The first and second chambers 1840, 1842 differ in size accordingto the size of the washer that is to be housed within it, i.e. the firstchamber 1840 is smaller than the second chamber 1842 because the firstwasher 1820 is smaller than the second washer 1822.

The cylindrical shafts 1824 of the first and second lock washers 1820,1822 have a diameter substantially the same as that of the circularbushes 1852 of the washer retainer 1850, and are configured to bereceived and retained by the circular bush 1852 in a snap-fitconfiguration. The snap-fit configuration is provided by the entrance ofthe circular bush 1852 being narrower than the diameter of thecylindrical shaft 1824. The slots 1854 of the washer retainers 1850 areconfigured to allow the entrance to be flexed open to increase the easewith which the first and second lock washers 1820, 1822 can be pushedthrough the entrances and assembled to the housing 295. Once assembledwithin the first and second chambers 1840, 1842 of the housing 295, thefirst and second washers 1820, 1822 can pivot back and forward around acentral axis that runs through the cylindrical shaft 1824.

The core member 340 is configured to pass through the core openings 1860of the housing 295 and the apertures 1876 of the first and secondwashers 1820, 1822. Application of a tension force to the core member340 causes the first and second lock washers 1820, 1822 to pivot backand/or forward between a locked position and/or open position. FIGS. 99and 100 show the directional lock in a locked configuration in which aforce is applied to the core member 340 in a direction towards the leftside of the figure (as indicated by the arrow). The force applied to thecore member 340 in this configuration causes the first and second lockwashers 1820, 1822 to pivot in an anti-clockwise direction, such thatthe path of the core member 340 through the directional lock 1800 isnon-linear or tortuous and movement of the core member 340 isrestricted. FIGS. 101 and 102 show the directional lock in an openconfiguration in which a force is applied to the core member 340 in adirection towards the right side of the figure (as indicated by thearrow). In this configuration, the first and second lock washers 1820,1822 are pivoted in a clockwise direction such that the circularapertures 1876 and core openings 1860 are aligned in a substantiallystraight line. This provides a smooth path for the core member 340 to bepulled substantially freely through the directional lock 1800.Additional particulars of the operation of the directional locks 1800are described above and in Applicant's PCT Application Publication No.WO2014/175752.

Summary of Features of Fourth Embodiment

Aspects of the fourth embodiment nasal mask interface, in someembodiments, may provide the following advantages or features:

-   -   A nasal mask interface that can be used with automatically        adjusting headgear (or any single side strap type headgear)        without the need for a forehead T-piece component,    -   Yoke 208 enables the headgear 250 to be removably connectable to        the seal housing 204 and nasal seal 202,    -   Under-nose support 224 in combination with a lower-profile or        shorter nasal seal and ribs 241 contribute to increases mask        stability on the user's face during use,    -   The low-profile or shorter height of the nasal seal means that        the seal contacts the user's nasal bridge at a lower position        that conventional nasal seals and this is generally less        intrusive,    -   Removably connectable conduit frame 211 is symmetrical and        allows the conduit frame to be connected in either of two        orientations,    -   The secondary seal lip (e.g. including 284 e, 284F) at the end        284A of the central gripping portion 284 of the conduit frame        211 assists in creating a back-up seal at the connection of the        conduit frame into the seal housing.

Fifth Embodiment—Various Alternative Nasal Mask Interface Configurations

Various forms of a fifth embodiment nasal mask interface assembly willnow be described with reference to FIGS. 103-149 . The various forms ofthe fifth embodiment nasal mask interface are similar in configurationand construction to the fourth embodiment generally, although there aredifferences. The following description will focus on the differencesbetween the embodiments. It would be appreciated that the variousalternatives and configurations described with reference to the fourthembodiment or other embodiments disclosed may also apply to the fifthembodiment forms.

First Nasal Mask Interlace of the Fifth Embodiment

Referring to FIGS. 103-117 , the first form 400 of the fifth embodimentnasal mask assembly will be described. As with the fourth embodiment,the nasal mask interface 400 comprises a nasal seal 402 coupled to aseal housing 404 and a yoke 408 received within a yoke channel 466 ofthe seal housing 404. As shown in Figure in 104, the nasal seal 402comprises an under-nose support 424 that extends within the mask cavity.As with the fourth embodiment, the first form nasal mask interface 400may connect to a headgear assembly of the type previously described viathe yoke 408 attachment.

In this embodiment, the central lower part or portion of the outer sideof the seal housing 404 comprises an integral inlet aperture 465. Inthis embodiment, the inlet aperture 465 is an oval protrusion orextrusion from the seal housing and is configured to connect or coupledirectly or indirectly to a gases supply conduit to supply a flow ofgasses into the mask cavity when in use. In this embodiment, anarrangement of bias vent holes 412 are provided in an array about theperiphery of the inlet aperture protrusion 465. The array of bias flowapertures 412 may extend around the entire periphery of the inletaperture protrusion 465 or a portion or portions of the peripherydepending on the embodiment.

Referring to FIGS. 107-110 , the connection of the yoke 408 to the sealhousing 404 will be described in further detail. In this embodiment, theyoke channel 466 is modified (relative to the fourth embodiment) in thatit provides larger singular locating features 468 on each lateral sideof the yoke channel 466 which are shaped and dimensioned to receivecomplementary portions of the thicker lateral regions 410 of the yoke408.

In this embodiment, a lower portion of the rear surface of the yokechannel 466 is provided with a recessed elongate channel 414 that isshaped and dimensioned to receive a complementary shaped elongateprotrusion or rib 416 located along the bottom of the rear surface of athinner central region 412 of the yoke 408. In particular, theprotrusion 416 of the yoke is configured to engage with an interferenceor friction fit into the complementary recess channel 414 of the yokechannel 466 to thereby couple the yoke 408 to the seal housing 404.

Referring to FIGS. 112 and 113 , in this first form of the fifthembodiment, the nasal seal 402 is provided with a channel 418 on itsouter seal housing connecting edge. This channel 418 is configured toengage with a complementary shaped and dimensioned ridge 420 extendingabout the opening of the seal housing 404 (see FIG. 110 ). The couplingof the nasal seal 402 to the seal housing 404 can be seen in thecross-sectional view of FIG. 114 , in particular, the coupling of theseal housing ridge 420 into the complementary channel 418 of the nasalseat. It will be appreciated that this configuration may be invertedwith the channel being provided on the seal housing 404 and theprotruding ridge being provided on the nasal seal 402, in alternativeembodiments.

Referring to FIGS. 111 and 112 , the lower central connecting portion419 of the under nose support 424 is similar to that of the fourthembodiment. The lateral connections 421 of the main lateral portion orband 422 of the under-nose support 424 connects directly to the lateralouter side wall portion of the nasal seal in the region of the channel418. In this embodiment, the lateral connections of the main lateralband 422 are lower within the nasal seal relative to the fourthembodiment and this provides a generally flatter curvature to the mainlateral band 422 in the central region of the mask cavity relative tothe fourth embodiment.

Second Form Nasal Mask Interface of Fifth Embodiment

With reference to FIGS. 118-128 , a second form nasal mask interface 450of the fifth embodiment will be described. The second form nasal maskinterface 450 is similar to first form, and like reference numeralscorrespond to like components.

The main difference in the second form nasal mask interface relates tothe configuration of the yoke 451 and yoke channel 452. In this secondform, the yoke channel 452 does not provide any specific locatingfeatures. Rather, the yoke channel 452 is configured to securely receiveand retain the yoke 451 via an interference fit between the surfaces ofthe channel 452 and the abutting outer surfaces of the yoke 451. Inparticular, with reference to FIG. 128 , the maximum height of the yokeas indicated at 453 is larger than the corresponding width of the yokechannel opening. A force is required to deform the yoke sufficiently topress it into the yoke channel 451 to create a semi-permanentinterference fit connection.

Third Form Nasal Mask Interface of Fifth Embodiment

With reference to FIGS. 129-139 , a third form of the fifth embodimentnasal mask interface will be described.

The third form nasal mask interface is similar to the first and secondforms, and like components use like reference numerals. The third formnasal mask interface assembly utilises an interference fit to couple theyoke 451 into the yoke channel 454 of the seal housing 404 like in thesecond form nasal mask interface. However, the shape and configurationof the yoke channel 454 of the seal housing 454 in the third form isaltered to angle the longitudinal axis of the yoke 451 upwardly toenable to provide an improved headgear vector. The angular offset orinclination of the yoke 451 upwardly is provided by the shape of theyoke channel 454 and the lateral cutout formations 453 provided at theside surfaces of the channel as shown on FIG. 133 . Referring to FIG.130 , the horizontal orientation of the longitudinal axis of the yoke451 is shown at 456 and this is the orientation of the first and secondforms of the nasal mask interface. The inclination of the yoke angle isshown with the longitudinal axis 457 of the yoke 451 in the third form,with the angular inclination indicated at 455. In this form, the angleof inclination is approximately 5°, although it will be appreciated theangle may be varied as desired.

Referring to FIGS. 130 and 137-139 , the nasal seal 402 of the thirdform also comprises variations relative to the previous forms. The thirdform nasal seal 402 has a thickened upper lip region as indicated 458 inFIG. 130 relative to the thinner upper lip region 459 of the second formembodiment shown in FIG. 119 . This provides for more compression in thebottom or upper lip region of the nasal seal in use and generally aflatter smoother transition to the contacting surface of the nasal seal.

The lower connecting portion 460 of the under-nose support 424 is alsothinner laterally at the connecting edge of the nasal aperture asindicated at 461 in FIG. 137 relative to the wider connection shown at462 in FIG. 121 of the second form. The lateral connections 462 of themain lateral band of the under-nose support 424 are also thicker andextend further into the nasal seal from the connecting channel edge 464as shown in FIG. 139 . For example, the connections 462 may integrallycouple to the channel connecting edge 464 of the nasal seal and aportion of the inner surface of the sidewall. In some embodiments, thelateral connections 462 may also couple with or extend to a portion ofthe inner surface of the contacting surface of the nasal seal.

In this third form, the length of the under-nose support 424 stemmingfrom the connecting edge of the nasal aperture to the rear edge of themain lateral hand 465 has been lengthened to accommodate longer noses.By way of example only, the length shown at 463 may be approximately22.8 mm compared with, for example, 17.9 mm in the first and secondforms of the fifth embodiment.

Fourth Form Nasal Mask Interface of the Fifth Embodiment

Referring to FIGS. 140-149 , a fourth form nasal mask interface 470 willbe described in further detail. The fourth form nasal mask interface 470is substantially similar to the third form nasal mask interface 460 andlike components have like reference numerals.

The first main difference in the fourth form as a mask interface 470relative to a third form is that the bias flow vent 471 has been movedfrom the inlet aperture 465 to the upper central region of the sealhousing 404 above the yoke channel. As shown, the bias flow ventcomprises a cluster or arrangement of tightly spaced apertures or holesas indicated at 471.

Referring to FIGS. 146-149 , the fourth form nasal mask interfacecomprises a nasal seal 402A having a modified geometry that provides aflatter contacting surface. In particular, with reference FIG. 149 , acomparison between the third form nasal seal 402 and the fourth formnasal seal 402A is shown. As depicted, the upper region, including thenasal bridge region of the nasal seal, and the lower upper lip region ofthe nasal seal have been brought forward relative to the third formnasal seal 402 to provide an overall flatter sealing surface thatprovides more cushioning.

Additionally, the length of the under nose support extending from thecentral connector at the nasal aperture edge to the rear edge of themain lateral band as indicated at 474 in FIG. 148 has been furtherlengthened relative to the third form nasal seal to a length ofapproximately 26.49 mm, compared with 22.8 mm in the third form nasalseal.

Sixth Embodiment

Referring to FIGS. 150-154 , a sixth embodiment of the nasal maskinterface 500 will be described. The substantive configuration of thenasal mask interface 500 is similar to the previous embodiments and inparticular to the fourth form 470 and like numerals represent likecomponents. The following description will focus on the maindifferences, and it will be appreciated that the alternatives discussedwith reference to the previous embodiments may also be applied to thissixth embodiment.

The primary difference with the nasal mask interface 500 compared withthe fourth form 470 is that the seal housing 504 has been reconfiguredby swapping the position of the yoke connection channel 454 and inletaperture or conduit connector 465. In particular the conduit connector465 is positioned in an upper central region of the seal housing abovethe yoke channel that receives the yoke 451. The yoke channel (notvisible) is similar to the yoke channel 454 of the fourth form nasalmask assembly 470. In some embodiments, the lower yoke positioning onthe seal housing may limit the amount of the frame rolling up on theuser's face.

The nasal mask interface 500 also comprises an alternative bias eventarrangement. In this embodiment, two bias event aperture clusters 501are provided in the upper lateral regions on the seal housing on eitherside of the inlet conduit 465.

Seventh Embodiment

With reference to FIGS. 155-462 , various alternative forms of a nasalseal for use in the nasal mask assembly will be described. As will beappreciated by a skilled person, the alternative forms of nasal seal ofthis seventh embodiment can be used with any of the embodiments of thenasal seal interface described, in particular any of the various formsof seal housing, yoke assembly and connection, and headgear assemblies.

First Form Nasal Seal of the Seventh Embodiment

Referring to FIGS. 155-157 , a first form nasal seal 600 will bedescribed. The first form nasal seal 600 of this embodiment is similarto the previous nasal seals described and includes an under-nose supportindicated at 601. The primary difference with this nasal seal 600 isthat it is provided with lateral wings or flaps 602 along at least aportion of the lateral sides of the contacting surface 603. In thisembodiment, the winged portions 602 are located at approximately themidway or middle region of the lateral sides of the nasal seal. Thewings 602 are shaped and configured to provide additional contactingsurfaces that are configured to engage the cheekbone/nasal area of theuser to increase stability, and the increased footprint of the contactsurface of the nasal seal on the user's face assists in reducing rollingor rocking from occurring in use in some embodiments. With reference toFIG. 157 , each of the wings 602 comprises a connecting portion 602Athat couples to a side wall portion of the nasal seal rearward of thecontacting surface 603, and an extension portion 602B that extendsforwardly of the contacting surface 603 to provide the winged contactingsurfaces on each lateral side of the nasal seal. The winged contactingportion 602 provide added support to prevent the nasal mask from rollingup the face of a user.

Second Form Nasal Seal of the Seventh Embodiment

The second form nasal seal 610 is similar to the first form 600 in thatit comprises lateral winged portions 604 that extend from the lateralside of the nasal seal. Compared to the first form nasal seal 600, thewings 604 are longer and adapted to conform with the flat area of thecheekbone/nasal area. As shown, in FIG. 161 the curved or contouredprofile of the winged regions is adapted to suit the contour of theuser's face. As with the first form, the wings 604 comprise a connectingportion 604A that couples the wing to the lateral side of the nasal sealand an extension or contacting portion 604B that is configured tocontact the cheekbone/nasal area of the user's face to stabilise thenasal mask on the user's face and prevent rolling as with the firstform.

Referring to FIG. 162 , a nasal mask interface comprising the secondform nasal seal 610 with the wings 604 is shown secured to the head of auser via a headgear assembly of the type previously described. As shown,the winged regions 604 may be loosely coupled or tethered to a strap ofthe headgear assembly, such as the side or front strap 252 on each sideof the nasal seal. In an embodiment, the wings may be provided with acoupling or connection mechanism at or towards the end of wing 604 forcoupling to the side strap 252. In one form, the connector 606 may be aloop member or similar through which the side strap 252 extends tothereby loosely couple or tether the side strap to the winged portion604 of the nasal seal. In other forms, the wings 604 may be de-coupledor untethered from the side straps 252.

Eighth Embodiment

With reference to FIGS. 163-170 , various alternative forms of a nasalseal for use in the nasal mask assembly will be described. As will beappreciated by a skilled person, the alternative forms of nasal seal ofthis eighth embodiment can be used with any of the embodiments of thenasal seal interface described, in particular any of the various formsof seal housing, yoke assembly and connection, and headgear assemblies.

First Form Nasal Seal of the Eighth Embodiment

Referring to FIGS. 163 and 164 , the first form nasal mask interface 700is shown in FIG. 163 with the nasal seal 701, seal housing 702, andgases supply conduit 703, In this first form of the eighth embodiment,the nasal mask interface additionally comprises a forehead supportcomponent indicated at 704. The forehead support component is configuredto engage with the user's forehead between or above their eyebrowsshould the mask roll or start to roll up the face and counteracts thisrolling force. In particular, the dimension and angular orientation ofthe forehead support 704 is such that in rest or normal use the foreheadsupport does not engage or is displaced from the user's forehead, andonly engages so as to counteract any upward rolling of the nasal maskduring use should that occur.

In this first form of the eighth embodiment, the forehead support 704 iscentrally provided above the nasal bridge region of the nasal seal. Inone form, the forehead support 704 may be coupled to extend exclusivelyfrom the seal housing 702, or exclusively from the nasal seal 701, or inyet a further alternative may be coupled to extend from both an upperregion of the seal housing 702 and nasal seal 701.

The forehead support 704 may be an integral part of the seal housing 702and/or nasal seal 701, or alternatively may be formed separately andcoupled or connected to the seal housing 702 and/or nasal seal 701. FIG.164 shows the forehead support 704 with a contacting region 704A locatedat or toward the end of the forehead support component, which in thisform is substantially elongate. The first form nasal mask interface 700can be seen worn by a user in FIG. 164 with a nasal mask interface beingcoupled via a headgear assembly of the type previously described coupledto the nasal mask interface by the yoke 706. The side strap 705 of theheadgear assembly can be seen in FIG. 164 .

Second Form Nasal Seal of the Eighth Embodiment

Referring to FIGS. 165-170 , a second form 710 nasal seal for use in thenasal mask interface is shown. The nasal seal 710 is substantiallysimilar in configuration to the previous nasal seals described. Aprimary difference is that the nasal seal is provided with a supportprotrusion 712 that extends upwardly from the apex of the seal. Thesecond form nasal seal 710 is shorter in height than the first formnasal seal 700, and the support protrusion 712 is configured tocounteract rolling up of the nasal mask in use by contacting the nasalbridge region of the user's face, rather than the forehead region likein the first form nasal seal 700.

As shown, the support protrusion 712 is integrally formed and extendsfrom an outer upper side of the nasal seal up and over the apex of thenasal bridge region of the contacting surface indicated at 711. As shownin FIG. 167 , the support protrusion in this embodiment generally tapersin thickness from the nasal seal connecting ends toward the upperextremity of the support protrusion.

Referring to FIGS. 169 and 170 , the nasal seal is shown in place on auser with the remainder of the nasal mask interface assembly omittedfrom view for clarity. As shown, in rest and normal use the uppersupport protrusion 712 is configured to be offset or displaced from theuser's nasal bridge. It is only if the nasal mask starts to roll orpivot up the user's face in use that the support protrusion 712 isrocked or pivoted inwardly toward the user's nasal bridge region tothereby counteracts the rolling force. In this embodiment, the in restdisplacement of the support protrusion 712 may be approximately 3 mmfrom a user's nasal bridge.

Ninth Embodiment

With reference to FIGS. 171-185 , various alternative forms of nasalseal for use of a nasal mask interface will be described. The variousforms of nasal seal may be used with any of the described nasal maskinterface assemblies, as will be appreciated by a skilled person.

First Form Nasal Seal of the Ninth Embodiment

Referring to FIGS. 171-174 , the first form nasal seal 750 of the ninthembodiment is substantially similar to the previous nasal sealsdescribed and includes an under-nose support indicated at 752. The firstform nasal seal 750 additionally comprises thickened regions in theupper lateral side portions of the contacting surface as indicated at754 which add support to the upper region of the nasal seal or cushion750. As shown, the thickened regions 754 are located proximal to oradjacent either side of the nasal bridge region of the contactingsurface indicated at 751.

The first form nasal seal 750 further comprises a pair of support ribs756 located within the thickened region 754, The support ribs 756 extendat an orientation that is substantially radial relative to the centreregion or nasal aperture of the nasal seal, rather than horizontally orvertically. The support ribs 756 add support to the upper region of thenasal seal from the inner surface of the nasal seal within the maskcavity and assist in reducing the upwards roll of the nasal maskinterface in use.

With reference to FIG. 174 , the support ribs are located above thelateral connections 758 of the under nose support 752. In other words,the support ribs 756 in this form are isolated from the under nosesupport connections 758, As shown, the support ribs 756 are connected toa portion of the side wall of the nasal seal including a portion of thecontacting surface but terminating prior to the thinned edge region atthe periphery of the nasal aperture.

In this embodiment, the support ribs 756 on the inside of the nasal sealhave an angular orientation relative to the vertical centre lineextending through the nasal seal. In this embodiment, the angularorientation indicated at 760 may be in the range of approximately 50° toapproximately 70°, preferably approximately 60°, in other words the ribshave an angular orientation of approximately 60° relative to thevertical centre line extending through the nasal seal.

Second Form Nasal Seal of the Ninth Embodiment

Referring to FIGS. 175-182 , the second form of the nasal seal of theninth embodiment will be described.

The second form nasal seal 770 of the ninth embodiment comprises analtered geometry relative to the first form nasal seal 750. Inparticular, the second form nasal seal 770 is shorter vertically, forexample by approximately 10 mm. The nasal seal otherwise has similarconfiguration to the previous nasal seals described. Referring to FIG.175 , the overall height of the second form nasal seal 770 as indicatedat 772 is approximately 47 mm, and the overall width of the nasal sealas indicated 774 is approximately 59 mm. Referring to FIG. 177 , theoverall depth of the second form nasal seal 770 as indicated 776 isapproximately 39 mm. In this embodiment, the ratio of the overall heightto width is in the range of approximately 1:1 to approximately 1:1.4,preferably approximately 1:1.3. In this embodiment, the ratio of theoverall height to overall width to overall depth is in the range ofapproximately 1:1:0.6 to approximately 1:1.4:1, preferably approximately1:1.3:0.8.

The contacting surface of the nasal seal is indicated at 771 and theouter side comprising the seal housing aperture is indicated at 773.

Referring to FIG. 179 , the difference between the upper contactingpoint of the nasal seal of the first and second forms of the ninthembodiment on the user's nasal bridge can be seen. The nasal bridgecontacting point for the second form nasal seal 770 is indicated at 777,and this is below the typical contacting point on the nasal bridge ofthe taller first form nasal seal as indicated at 778. The reducedvertical height of the second form nasal seal 770 enables it to contactthe nasal bridge at a much lower point, for example to contact a portionof the nasal bridge within the area or region of the nasal bridgeextending between the tip of the nose and halfway up or to the center ofthe nasal bridge. This lower contacting region relative to conventionalnasal seals may be more uniform between multiple users and thereforeincreases the percentage of the population being able to successfullyuse the nasal mask.

Referring to FIGS. 181 and 182 , the first form nasal seal 750 is shownoverlaid onto the shorter second form nasal seal 770 to show thedifference in geometry for comparison.

Third Form Nasal Seal of the Ninth Embodiment

With reference to FIGS. 183-185 , a third form nasal seal 780 of theninth embodiment will be described.

The third form nasal seal 780 in this embodiment is similar in size andshape to the shorter second form nasal seal 770. The main difference isthat the third form nasal seal 780 additionally comprises support ribs782 on the inner surface of the nasal seal. In particular, the mainlateral portion of the under nose support 781 at each lateral endconnects to a respective support rib 782. As shown, the support ribs 782have a substantially vertical or near vertical orientation. The undernose support and its connection to the support ribs is similar inconfiguration to that described with reference to the nasal seal of thefourth embodiment.

In this third form nasal seal 780, the ribs 782 strengthen theconnection of the under nose support within the nasal seal and alsoperform the dual function of providing structural support to the upperregion of the nasal seal. In this third form, the under-nose support ismore squarish in shape, rather than U-shaped. In particular, the mainlateral portion comprises a substantially flat or horizontal centralregion 783 and two substantially vertical lateral portions 784 extendingupwardly from a respective end of the central region.

Tenth Embodiment

With reference to FIGS. 186-205 , various forms and configurations ofseal housing and conduit frame of the nasal mask interface will bedescribed. It will be appreciated that these various forms of sealhousing and conduit frame variations may be incorporated into thevarious embodiments of the nasal mask assembly described to providealternative configurations.

First Form Conduit Frame Configuration of the Tenth Embodiment

Referring to FIGS. 186-189 , the first form conduit frame 800 is ahollow ovular body that extends between the housing connecting end 801and a gases supply conduit connecting at 802. As shown, the main bodyhas a curved surface profile that corresponds with the surface profileof the seal housing 804 about the periphery of the aperture 806 intowhich the conduit frame connects. In particular, the conduit frame has asurface profile that co-operates with the surface profile of the sealhousing to provide a blended or continuous surface at the interfacebetween the two components when assembled together.

The first form conduit frame 800 provides a pair of scalloped gripregions on the lateral sides of the main body toward the conduitconnecting end 802 as indicated at 808 (only one visible). The sealhousing connecting end 801 is provided with protrusions as indicated at810 on the upper and lower surface for snap fit engagement withcomplementary recess or grooves 812 provided in the surfaces of theaperture of the seal housing 804 similar to the configuration describedwith respect of the fourth embodiment.

With reference to FIG. 188 , the main body of the conduit frame 800 isconfigured to provide an approximately 30° decline angle as indicated at814 relative to the horizontal. In particular, the axis at the conduitend at 802 is angled or offset relative to the axis of the aperture atthe seal housing connecting end 801. It will be appreciated that theangle may be varied.

Second Form Conduit Frame Configuration of the Tenth Embodiment

With reference to FIGS. 190-193 , the second form conduit frame 820 ofthe tenth embodiment will be described. In this embodiment, the conduitconnecting end 821 of the conduit frame 820 is again provided withscalloped grip regions or portions 822. The seal housing connecting endindicated at 823 is larger and comprises winged portions that overlapwith portions of the external surface of the seal housing 824 adjacentthe air inlet conduit protrusion 825 of the seal housing.

As shown in FIG. 191 , the conduit frame comprises a complementaryconduit portion having one or more protrusions or grooves 826 thatcomplement for snap fit or interference engagement with complementaryprotrusions or grooves 827 provided on the conduit protrusion 825 of theseal housing 824.

As shown in FIG. 192 , the winged lateral portions of the conduit frameat the seal housing connecting end 823 may comprise apertures 828. Theseapertures may provide a surface for diffuser mats to provide a bias ventif the seal housing is provided with aligned complementary apertures.

Third Form Conduit Frame Configuration of the Tenth Embodiment

With reference to FIGS. 194-197 , a third form conduit frame 830 will bedescribed. The third form conduit frame 830 is substantially similar tothe second form conduit frame 820. The main difference is that the sealhousing 835 is provided with a larger inlet aperture opening 833 thatentirely receives the winged regions 832 of the conduit frame to providea blended surface. In other words, there is no overlap with the wingedregion of the conduit frame onto the external surface of the sealhousing like in the second form configuration.

As shown in FIGS. 194-197 , the lateral edges of the winged regions ofthe conduit frame may be provided with protrusions or grooves 832 thatare configured to snap fit or otherwise engage with complementarygrooves or protrusions 833 provided within the inner peripheral surfacesof the aperture 831 of the seal housing 835.

Fourth Form Conduit Frame Configuration of the Tenth Embodiment

With reference to FIGS. 198-201 , a fourth form conduit frame 840 willbe described. The fourth form conduit frame 840 is provided with aconduit at the seal housing connecting end as indicated at 843 that isreceived within a complementary conduit 844 of the seal housing 842. Theconduit portion 843 of the conduit frame comprises either protrusions orgrooves 845 on the upper and/or lower surfaces or other surfaces thatengage with complementary aligned protrusions or grooves 846 via theinternal surface of the conduit aperture 844 of the seat housing 842.

Referring to FIG. 201 , surrounding the lateral portions of the conduitportion 843 are winged regions 847 that extend from the lateral sides ofthe conduit frame on either side of the conduit portion 843. Thesewinged regions or portions 847 are received within complementaryrecessed regions 848 provided on the lateral sides of the inlet of theseal housing 842. The external surface profile of the winged regions 846and main body generally of the conduit frame at the seal housingconnecting end is configured to marry or blend in with the surfaceprofile of the seal housing in the regions surrounding the inletaperture such that there is a seamless or blended surface at theinterface of the two components when assembled together as shown in FIG.198 .

Opposite to the seal housing connecting end of the conduit frame isprovided gripping tabs or protrusions 849 that extend laterally from thesides of the conduit frame at the gases supply conduit connecting end850 of the conduit frame. These gripping tabs 849 allow the user to pullthe conduit frame from the seal housing when desired. They also mayassist in inserting the conduit frame into the seal housing duringassembly.

Fifth Form Conduit Frame Configuration of the Tenth Embodiment

Referring to FIGS. 202-205 , a fifth form conduit frame 850 of the tenthembodiment will be described.

The fifth form conduit frame 850 is similar to the fourth form conduitframe 840. The main differences are that the gripping tabs are replacedwith a series or rows of gripping protrusions as indicated at 852 at thegases supply conduit connecting end the conduit frame 850. The wingedregions 853 and conduit portion 855 at the seal housing connecting endis symmetrical relative to a horizontal plane extending through axis 856indicated at FIG. 204 .

The fifth form conduit frame 850 has an angular offset between the sealhousing connecting end 858 and the gases supply conduit supplyconnecting end 859. In this embodiment, the axis extending from theconduit connecting end 859 is offset at a declined angle ofapproximately 40° relative to the axis extending from the seal housingconnecting end 858, although this angle may be altered as appreciated.

With the symmetrical seal housing arrangement, the conduit frame 850 maybe connected into the seal housing 862 in either of two orientationsthat are rotated 180° relative to each other. Additionally, the angledoffset at the conduit connecting end 859 enables the conduit frame to beassembled into the seal housing. 862 in a first orientation in which theconduit connecting end 859 is angled downwardly to allow the conduit toface or extend toward the user's feet, or an alternative may beinstalled in a second orientation such that the conduit connecting end856 is angled upwardly such that the conduit can extend upwardly in thedirection of the user's forehead.

Further Alternative Embodiments

The following describes various alternative embodiments orconfigurations of the interface. It will be appreciated that any one ormore of these embodiments or configurations either alone or incombination may be applied to the general embodiments described above.

Full Lace Embodiment

The embodiments described above with reference to FIGS. 2A-205 relate tonasal seal interfaces that are configured to seal about the nose of auser. However, it will be appreciated that such embodiments may also beadapted into full face or oronasal masks that are configured to sealabout both the nose and mouth of a user such that therapy gases can bedelivered to the user's airways via the nose and mouth. By way ofexample only, FIG. 206 shows an eleventh embodiment in the form of afull face interface 102E. The full face seal 102E is similar to thatdescribed in the third embodiment 102D of FIGS. 30-34 and comprises asingle band under-nose support 124D configuration. The full-face seal102E is substantially similar in configuration although has a largercontacting surface 120E. The enlarged contacting surface 120E isconfigured to seal about the users nose and mouth, i.e. is shaped tocircumscribe about both the nose and mouth. The upper region 125 at ortoward the nasal bridge region is substantially similar to thatpreviously described, but the side cheek regions 123 extend furtherdownwardly and are connected by a lower region 121E that is configuredto seal below the users mouth, such as proximal to their chin. With thislarger contacting surface, both the user's nose and mouth can beencapsulated within the seal 102E,

Under-Nose Support Formed of a Different Material to the Seal

In the above embodiments described with reference to FIGS. 2A-205 , theunder-nose support is typically integrally formed and an integral partof the nasal seal. For example, the nasal seal and its under-nosesupport are integrally molded as a single unit from silicone or othersuitable material. Alternatively, the nasal seal and under-nose supportare molded as separate parts initially then permanently coupled orconnected together, such as by adhesive or welding or similar, to forman unitary nasal seal component.

In alternative embodiments, the under-nose support may be formed of amaterial that is different to the nasal seal. For example, the nasalseal may be formed of silicone, but the under-nose support may be formedof a different material such as, but not limited to, a textile material,foam material, neoprene, Breath-o-Prene® material, thermoplasticpolyurethane (TPU), The under-nose support can then be permanentlycoupled or connected into the nasal seal, such as by adhesive or weldingor similar, to form a unitary nasal seal component.

Non-Fixedly Connected Under-Nose Support and Other ConnectionConfigurations

In the above embodiments described with reference to FIGS. 2A-205 , theunder-nose support is typically fixedly connected within the nasal seal,such as being integrally formed or otherwise permanently connected intothe nasal seal. In alternative embodiments, the under-nose support maybe removably or releasably connected into the nasal seal by a releasableconnection assemblies at the connection points or locations of the nasalseal previously described.

In further alternative configurations, the under-nose support may befixedly or releasably connected or coupled to non-seal structures orcomponents of the interface. For example, the under-nose support may befixedly or releasably connected to the seal housing or rigid clipcomponents or frame components, depending on the configuration. Aspreviously mentioned, the under-nose support may be formed of anysuitable material including, but not limited to, silicone, textile, foammaterial, neoprene, Breath-o-Prene® material, or TPU.

The foregoing description of the invention includes preferred formsthereof. Modifications may be made thereto without departing from thescope of the invention as described by the accompanying claims.

1-40. (canceled)
 41. A nasal mask interface assembly comprising: a sealhousing; a flexible nasal seal connectable to the seal housing, theflexible nasal seal at least partially defining a mask cavity, theflexible nasal seal extending between a face-contacting side and anouter side, the flexible nasal seal comprising: a contacting surfacecomprising an edge, the edge defining a nose-receiving opening into themask cavity, and the edge being configured to seal around a nose of auser; and an under-nose support fixedly connected within the flexiblenasal seal, the under-nose support extending into the mask cavity, theunder-nose support having a contact surface, the contact surface beingoriented to contact at least a portion of an under-nose surface of theuser; headgear comprising a single left side strap and a single rightside strap, the single left side strap and the single right side strapbeing capable of extending over a left ear and a right ear of the userrespectively; and a yoke releasably connectable to the seal housing, theyoke comprising a pair of opposing distal ends, each of the pair ofopposing distal ends of the yoke being connectable to a correspondingend of one of the single left side strap and the single right side strapsuch that the headgear is connected to the yoke to define a closed loopheadgear system.
 42. The nasal mask interface assembly of claim 41,wherein the under-nose support comprises an elongate main lateralportion, the elongate main lateral portion connected to and suspendedbetween opposing sidewall portions of the flexible nasal seal such thatthe elongate main lateral portion extends laterally within the maskcavity.
 43. The nasal mask interface assembly of claim 41, wherein theunder-nose support comprises an elongated strip or band of material, theelongated strip or band of material extending laterally across andwithin the flexible nasal seal between opposing sides of the flexiblenasal seal, the elongated strip or band of material being locatedrearwardly of the contacting surface, and the under-nose support beingconformable with a sling-like effect to the under-nose surface of theuser.
 44. The nasal mask interface assembly of claim 41, wherein theyoke is substantially elongate, the yoke comprising a strap connectorlocated at or near each of the pair of opposing distal ends of the yokesuch that there are a pair of strap connectors.
 45. The nasal maskinterface assembly of claim 44, wherein each of the pair of strapconnectors comprises an end cap to provide a pair of end caps, the pairof end caps located with one of the pair of end caps at each of the pairof opposing distal ends of the yoke, and each of the pair of end capsbeing non-removably connected to the corresponding one of the pair ofopposing ends of the yoke.
 46. The nasal mask interface assembly ofclaim 45, wherein each of the pair of end caps is over-molded onto abraided element of each of the single left side strap and the singleright side strap.
 47. The nasal mask interface assembly of claim 46,wherein the yoke defines a collector for core elements used in anautomatically adjustable headgear.
 48. The nasal mask interface assemblyof claim 47 further comprising core elements, wherein the core elementsextend within the braided element of each of the single left side strapand the single right side strap, and each of the pair of end capsconnect the braided element of each of the single left side strap andthe single right side strap and headgear to the yoke to define theclosed loop headgear system.
 49. The nasal mask interface assembly ofclaim 48, wherein the yoke comprises one or more directional locks thatinteract with the core elements that extend from each of the single leftside strap and the single right side strap of the automaticallyadjustable headgear.
 50. The nasal mask interface assembly of claim 49,wherein at least one of the one or more directional locks comprises awasher mechanism that frictionally engages with at least one of the coreelements during elongation of the automatically adjustable headgear, thewasher mechanism allowing relatively friction-free movement of the atleast one of the core elements during retraction of the automaticallyadjustable headgear.
 51. The nasal mask interface assembly of claim 49,wherein the one or more directional locks are adaptable between a lockedconfiguration and an open configuration.
 52. The nasal mask interfaceassembly of claim 51, wherein, in the locked configuration, a pathprovided for the core elements through the one or more directional locksis non-linear or tortuous and movement of the core elements isrestricted through the directional locks.
 53. The nasal mask interfaceassembly of claim 51, wherein, in the open configuration, a path isprovided for the core elements to be pulled substantially freely thoughthe directional locks.
 54. The nasal mask interface assembly of claim41, wherein the seal housing comprises a yoke channel and an exteriorsurface, the yoke channel extending laterally across the exteriorsurface of the seal housing, the yoke channel being capable ofreleasably receiving and retaining the yoke.
 55. The nasal maskinterface assembly of claim 41, wherein each of the single left sidestrap and the single right side strap can extend along sides or cheeksof a face of the user.